EPS-HEP2021 conference

26 Jul 2021, 00:00 → 30 Jul 2021, 19:00 Europe/Berlin

Zoom

Johannes Haller (Institut für Experimentalphysik, Universität Hamburg), Ties Behnke (FLC (Forschung an Lepton Collidern))

This is the 2021 edition of the EPS-HEP conference. The Indico agenda of the EPS-HEP2023 is here: https://indico.desy.de/event/34916/

 

The European Physical Society Conference on High Energy Physics (EPS-HEP) is one of the major international conferences that reviews the field every second year since 1971 and is organized by the High Energy and Particle Physics Divison of the European Physical Society. The latest conferences in this series were held in Ghent, Venice, Vienna, Stockholm, Grenoble, Krakow, Manchester, Lisbon, Aachen.

 

The 2021 European Physical Society conference for high energy physics will follow a purely online format. The organisation of the conference is hosted jointly by Universität Hamburg and by the research center DESY. The conference will feature plenary, review and parallel sessions covering all major areas and developments in high energy and particle physics, astroparticle physics, neutrino physics and related areas.

 

Please visit the main conference page for more information. 

---

Registration

We ask everyone to register for the EPS-HEP2021 conference, if you want to attend any of the sessions. Access to sessions will be possible using a key given to registered participants only. There will be no registration fee.

Abstract Submission

Participants to the conference are invited to submit abstracts for parallel session talks and for posters. Please follow the instructions at Call for Abstracts to submit and manage your abstracts. 

Important Deadlines

Registration
Opening	February 1, 2021
Closing	July 12, 2021
Modification deadline	July 19, 2021
Abstract submission
Opening	February 10, 2021
Closing	May 7, 2021
Acceptance notification	June 4, 2021

 

 

 

 

 

 

 

 

 

 

 

 

---

Monday, 26 July

T01: Astroparticle and Gravitational Waves: Part 1

Convener: Prof. Oliver Gerberding (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik))

1 Cold aberrations and locking of Central Interferometer of Advanced Virgo+

The target sensitivity of Advanced Virgo for O4 is about 90-120 Mpc for the BNS range. To achieve this, several hardware upgrades are under process. One of the most relevant concerns installation of the Signal Recycling Mirror, which forms an additional marginally stable cavity along with the power recycling cavity already present in Advanced Virgo. Therefore, to compensate for these (cold) optical aberrations, new Central Heating benches were installed by the TCS subsystem.
I will describe the installation and pre-commissioning of CO_2 central heating, which assists the lock of DRMI by compensating for the (cold) optical aberrations, and the procedure followed for locking the Dual Recycled Michelson Interferometer along with the tuning of CO_2 central heating.”

Speaker: Priyanka Giri (INFN Pisa)

EPS_HEP_Giri.pdf

2 The performance of the Virgo gravitational-wave detector during the O3 run (04/2019-03/2020) and the impact of the external environment

The Observation Run 3 (O3) is the longest data-taking period to-date for the LIGO-Virgo global network of ground-based interferometric gravitational-wave (GW) detectors. The GWTC catalog of transient GW events has already been updated for the first six months of the run (O3a: 2019/04/01 -> 2019/19/01) while the analysis of the last five months (O3b: 2019/11/01 -> 2020/03/27, after a one-month commissioning break) is ongoing. This talk will review the performance of the Virgo detector during the O3 run: sensitivity, duty cycle, noise stability and variations. It will in particular focus on the impact of the external environment on this performance: earthquakes, anthropogenic seismic noise, local weather at the EGO site, etc. The experience gained should allow the Virgo Collaboration to improve the robustness of its instrument against external disturbances and to develop improved strategies to mitigate their consequences. This work is ongoing during the current shutdown, besides major detector upgrades, prior to the start of the upcoming O4 run during summer 2022.

Speaker: Dr Nicolas Arnaud (IJCLab (UPSaclay and CNRS/IN2P3) and EGO)

20210726_EPS_O3VirgoPerf_impactExtEnv.pdf

3 Instrument science challenges of the Einstein Telescope

The Einstein Telescope (ET) is a planned third-generation gravitational wave observatory in Europe. The ET observatory is composed of three detectors that together form an equilateral triangle. Each detector consists of two interferometers, one optimised for low frequencies from 3 Hz to 30 Hz and another optimised for high frequencies from 30 Hz to 10 kHz. In order to reach its ambitious sensitive target ET will require significant technology advances compared to current facilities, from cryogenic suspensions to Newtonian noise subtraction. We have recently started the effort towards the technical design of the detectors and the infrastructure. In this talk I will provide a short overview of the unique challenges and plans of ET instrument science activities.

Speaker: Andreas Freise (VU Amsterdam and Nikhef)

Freise_ET_210726_small.pdf

4 Lunar Gravitational-Wave Antenna

Gravitational waves excite quadrupolar vibrations of elastic bodies. Monitoring these vibrations was one of the first concepts proposed for the detection of gravitational waves by Joseph Weber. At laboratory scale, these experiments became known as resonant-bar detectors, which form an important part of the history of GW detection. Due to the dimensions of these bars, the targeted signal frequencies were in the kHz range. It was also Weber who suggested to monitor vibrations of Earth and Moon to search for gravitational waves in the mHz band. His Lunar Surface Gravimeter was deployed on the Moon in 1972 by the Apollo 17 crew. A design error made it impossible to carry out the intended search for GWs, but the idea remains intriguing. We have proposed a new concept, the Lunar Gravitational-Wave Antenna (LGWA), based on Weber’s idea. LGWA would have a rich GW and multi-messenger science case with galactic binaries and massive black-hole binaries potentially closing the frequency gap between LISA and terrestrial GW detectors. It would also serve as a high-precision geophysical station shedding light on the interior structure of the Moon, the mechanisms of moonquakes, and the Moon's formation history. LGWA's key component is a next-generation, high-sensitivity seismometer to be deployed on the Moon. For its most sensitive realization, LGWA would have to be deployed in a permanent shadow near the north or south pole of the Moon to benefit from the natural cryogenic environment. This would improve the sensitivity of the seismometer and also provide a lower-noise environment due to the absence of thermally induced seismic events that were observed in large numbers by the Apollo seismometers. Powering of the seismic stations and data transfer pose additional challenges for such a deployment.

Speaker: Jan Harms (Gran Sasso Science Institute)

LGWA_EPS_JH.pdf

5 Upper limits on the amplitude of ultra-high-frequency gravitational waves from graviton to photon conversion

First experimental upper limits for stochastic ultra-high-frequency gravitational waves are obtained using data from existing facilities that have been constructed and operated to detect WISPs (Weakly Interacting Slim Particles). Using the graviton to photon conversion in the presence of their magnetic field, we exclude gravitational waves in the frequency bands from $\left(2.7 - 14\right)\times10^{14}$~Hz and $\left(5 - 12\right)\times10^{18}$~Hz down to a characteristic amplitude of $h_c^{\rm min}\approx6\times 10^{-26}$ and $h_c^{\rm min}\approx 5\times 10^{-28}$ at 95\% confidence level, respectively. This principle applies to all experiments of this kind, with prospects of constraining (or detecting), for example, stochastic gravitational waves background from light primordial black hole evaporation in the early universe.

Speaker: Aldo Ejlli (Cardiff University)

Aldo_Ejlli_EPS_HEP_26_07_2021.pdf

6 Searching for dark photon dark matter in the third observing run of LIGO/Virgo

We report results from a search for ultralight dark photon dark matter using data from the third observing run of Advanced LIGO and Virgo. This type of dark matter could directly couple to the interferometers and cause a time-dependent quasi-sinusoidal force on the mirrors proportional to the total proton plus neutron number, or just neutron number. We describe two methods to search for this interaction, one that cross correlates data from different detectors, and another that varies the analysis coherence time to account for the expected signal frequency spread and looks for excess power in each detector. We also compare our sensitivity to those from existing direct dark matter experiments for a wide range of dark photon masses.

Speaker: Andrew Miller (UCLouvain)

slides_darkphoton_eps_hep.pdf

T03: Dark Matter: Part 1

Convener: Laura Lopez-Honorez (Universite Libre de Bruxelles)

7 Dark matter from evaporating Black Holes

Primordial black holes might have existed in the early Universe and, via their evaporation mechanism (completed before Big Bang Nucleosynthesis), they might have released stable particles beyond the Standard Model. We discuss the possibility that such particles might constitute all or a fraction of the dark matter observed today, also considering the bounds on warm dark matter. If sufficiently light, stable particles from primordial black holes evaporation might provide a significant contribution to dark radiation.

Speaker: Isabella Masina

Masina-EPS-HEP-web.pdf

8 Dark matter and dark radiation from primordial black holes

Primordial black holes (PBHs) lighter than $10^9\,$g are at present mostly unconstrained, because they evaporate before Big Bang Nucleosynthesis (BBN). Hence, they can not represent a fraction of dark matter (DM). However, their evaporation products can leave an imprint on the early universe observables. In this talk, we will decribe how the public code BlackHawk has been adapted to compute the Hawking radiation of light PBHs with the addition of a dark sector particle. Depending on this particle mass, it can result in a contribution to warm DM or dark radiation. The first one is further constrained using structure formation thanks to CLASS and the second one contributes to $\Delta N_\text{eff}$, constrained by BBN and CMB (future) experiments. We conclude by giving the Hawking radiation constraints on light PBHs.

Speaker: Jérémy Auffinger (Institut de Physique des 2 Infinis - Lyon - FRANCE)

main.pdf

9 Shining Light on Dark Matter with Black Holes

What is dark matter, the mysterious predominant constituent of all matter in the Universe? As I will show, primordial black holes from the early Universe make an attractive non-particle dark matter candidate, with intimate connections to astronomical puzzles like the origin of heavy elements (gold) as well as ongoing boom in gravity wave and multi-messenger astronomy. In fact, primordial black holes from the general formation scenario of bubble multiverse might have already been seen by Subaru Hyper Suprime-Cam.

Speaker: Volodymyr Takhistov

EPS-HEP2021_Takhistov.pdf

10 Searches for dark matter with the ATLAS detector

The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS experiment has developed a broad search program for DM candidates, including resonance searches for the mediator which would couple DM to the SM, searches with large missing transverse momentum produced in association with other particles (light and heavy quarks, photons, Z and H bosons) called mono-X searches and searches where the Higgs boson provides a portal to Dark Matter, leading to invisible Higgs decays. The results of recent searches on 13 TeV pp data, their interplay and interpretation will be presented. Prospects for HL-LHC will also be discussed.

Speaker: Jonathan Bossio (CERN)

ATLASDMSearchesJonaBossioEPS2021.pdf

11 Dark Matter searches in CMS

Searches for dark matter at colliders are a powerful complementary probe to elucidate the nature of this hitherto unobserved form of matter. We present CMS searches for dark matter candidate particles and new mediators interacting with them. Various final states, topologies, and kinematic variables are explored utilizing the full Run-II data-set collected at the LHC. Furthermore, we interpret the results of the searches for direct dark matter production as well as visible decays of new mediators in the broader dark matter search landscape.

Speaker: Raman Khurana (Florida State University)

5-CMS_DM_Results_EPS2021.pdf

12 New sensitivity of LHC measurements to Composite Dark Matter

We present sensitivity of LHC Standard Model (SM) differential cross-section measurements for so-called “stealth dark matter” scenarios occurring in an SU(ND) dark gauge group, where constituents are charged under the SM and ND =2 or 4. The low-energy theory contains mesons which can be produced at the LHC and a scalar baryon dark matter (DM) candidate which cannot. We evaluate the impact of LHC measurements on the dark meson masses. Using existing lattice results, we then connect the LHC explorations to DM phenomenology, in particular considering direct-detection experiments. We show that current LHC measurements constrain DM masses in the 10s of TeV regime. We discuss potential pathways to explore these models further using LHC measurements.

Speaker: Louie Corpe (CERN)

6-LCorpe_CONTUR_EPS2021.pdf

T04: Neutrino Physics: Neutrino mass & properties

Convener: Bjoern Soenke Wonsak (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik))

13 The Singly-Charged Scalar Singlet as the Origin of Neutrino Masses

We consider the generation of neutrino masses via a singly-charged scalar singlet. Under general assumptions we identify two distinct structures for the neutrino mass matrix. This yields a constraint for the antisymmetric Yukawa coupling of the singly-charged scalar singlet to two left-handed lepton doublets, irrespective of how the breaking of lepton-number conservation is achieved. The constraint disfavours large hierarchies among the Yukawa couplings. We study the implications for the phenomenology of lepton-flavour universality, measurements of the $W$-boson mass, flavour violation in the charged-lepton sector and decays of the singly-charged scalar singlet. We also discuss the parameter space that can address the Cabibbo Angle Anomaly.

Speaker: Tobias Felkl (University of New South Wales)

talk-eps21-felkl.pdf

14 Modullar Invariance Approch to the Flavour Problem: Fermion Mass Hierarchies and Residual Modular Symmetries

We will discuss the approach to the flavour problem
based on modular invariance.
In modular-invariant models of flavour,
hierarchical fermion mass matrices may arise
solely due to the proximity of the modulus $\tau$
to a point of residual symmetry.
This mechanism does not require flavon fields, and modular
weights are not analogous to Froggatt-Nielsen charges.
We show that hierarchies depend on the decomposition
of field representations under the residual symmetry group.
We systematically go through the
possible fermion field representation choices which may yield
hierarchical structures in the vicinity of symmetric points,
for the four smallest finite modular groups, isomorphic
to $S_3$, $A_4$, $S_4$, and $A_5$, as well as for their double covers.
We find a restricted set of pairs of representations for which the
discussed mechanism may produce viable fermion (charged-lepton and quark)
mass hierarchies. After formulating the conditions for obtaining a viable lepton
mixing matrix in the symmetric limit, we construct a model in which both
the charged-lepton and neutrino sectors are free from fine-tuning.

Speaker: Serguey Petcov (SISSA/INFN, Trieste, Italy)

Petcov2507EPSHEP260721.pdf

15 A systematic approach to neutrino masses and their phenomenology

We propose a model-independent framework to classify and study neutrino mass models and their phenomenology. The idea is to introduce one particle beyond the Standard Model which couples to leptons and carries lepton number together with an operator which violates lepton number by two units and contains this particle. This allows to study processes which do not violate lepton number, while still working with an effective field theory. The contribution to neutrino masses translates to a robust upper bound on the mass of the new particle. We compare it to the stronger but less robust upper bound from Higgs naturalness and discuss several lower bounds. Our framework allows to classify neutrino mass models in just 20 categories, further reduced to 14 once nucleon decay limits are taken into account, and possibly to 9 if also Higgs naturalness considerations and direct searches are considered.

Speaker: Michael Schmidt (UNSW Sydney)

EPS_Michael_Schmidt.pdf

16 First Sub-eV Neutrino Mass Limit from the KATRIN Experiment

The KATRIN experiment is designed to measure the effective electron anti-neutrino mass $m_\nu$ with a sensitivity close to 0.2 eV by investigating the energy spectrum of tritium $\beta$-decay. After a brief introduction of the experiment, we will focus on the results from our second data taking phase which took place in autumn 2019. For this period, the source activity was increased by a factor of four with respect to the first campaign and around 4.2 million electrons were collected in the region of interest. A fit to this data including all dominant uncertainties yields $m^2_\nu = 0.26 \pm 0.34$ eV$^2$. This corresponds to an upper limit of $m_\nu < 0.9$ eV (sensitivity $m_\nu < 0.7$ eV) using the method of Lokhov and Tkachov. Finally, we will give a brief outlook on the upcoming measurement phases.

Speaker: Christian Karl (Max Planck Institute for Physics)

ckarl_21-07-26-epshep-katrin.pdf

17 Electromagnetic neutrino: The theory, laboratory experiments and astrophysical probes

We continue our discussions [1-4] on neutrino electromagnetic properties. In the present talk we start with a short introduction to the derivation of the general structure of the electromagnetic form factors of Dirac and Majorana neutrinos.

Then we consider experimental constraints on neutrino magnetic and electric dipole moments, electric millicharge, charge radii and anapole moments from the terrestrial laboratory experiments (the bounds obtained by the reactor MUNU, TEXONO and GEMMA experiments and the solar Super-Kamiokande and the recent Borexino experiments). A special credit is done to the most severe constraints on neutrino magnetic moments, millicharge and charge radii [5-9]. The world best reactor [5] and solar [6] neutrino and astrophysical [10,11] bounds on neutrino magnetic moments, as well as bounds on millicharge from the reactor neutrinos [7] are included in the recent issues of the Review of Particle Physics (see the latest Review: P.A. Zyla et al. (Particle Data Group), Prog. Theor. Exp. Phys. 2020, 083C01). The best astrophysical bound on neutrino millicharge was obtained in [12].

In the recent studies [13] it is shown that the puzzling results of the XENON1T collaboration [14] at few keV electronic recoils could be due to the scattering of solar neutrinos endowed with finite Majorana transition magnetic moments of the strengths lie within the limits set by the Borexino experiment with solar neutrinos [6]. The comprehensive analysis of the existing and new extended mechanisms for enhancing neutrino transition magnetic moments to the level appropriate for the interpretation of the XENON1T data and leaving neutrino masses within acceptable values is provided in [15].

Considering neutrinos from all known sources, as well as including all available data from XENON1T and Borexino, the strongest up-to-date exclusion limits on the active-to-sterile neutrino transition magnetic moment are derived in [16] .

A comprehensive analisys of constraints on neutrino electric millicharge from experiments of elastic neutrino-electron interaction and future prospects involving coherent elastic neutrino-nucleus scattering is presented in [17].

We also present results of the recent detailed study [18] of the electromagnetic interactions of massive neutrinos in the theoretical formulation of low-energy elastic neutrino-electron scattering. The formalism of neutrino charge, magnetic, electric, and anapole form factors defined as matrices in the mass basis with account for three-neutrino mixing is presented. Using the derived new expression for a neutrino electromagnetic scattering cross section [18], we further developed studies of neutrino electromagnetic properties using the COHERENT data [8] and obtained [9] new bounds on the neutrino charge radii from the COHERENT experiment. Worthy of note, our paper [9] has been included by the Editors Suggestion to the Phys. Rev. D “Highlights of 2018”, and the obtained constraints on the nondiagonal neutrino charge radii since 2019 has been included by the Particle Data Group to the Review of Particle Physics.

The main manifestation of neutrino electromagnetic interactions, such as: 1) the radiative decay in vacuum, in matter and in a magnetic field, 2) the neutrino Cherenkov radiation, 3) the plasmon decay to neutrino-antineutrino pair, 4) the neutrino spin light in matter, and 5) the neutrino spin and spin-flavour precession are discussed. Phenomenological consequences of neutrino electromagnetic interactions (including the spin light of neutrino [19]) in astrophysical environments are also reviewed.

The second part of the proposed talk is dedicated to results of our mostly recently performed detailed studies of new effects in neutrino spin, spin-flavour and flavor oscillations under the influence of the transversal matter currents [20] and a constant magnetic field [21,22], as well as to our newly developed approach to the problem of the neutrino quantum decoherence [23] and also to our recent proposal [24] for an experimental setup to observe coherent elastic neutrino-atom scattering (CEνAS) using electron antineutrinos from tritium decay and a liquid helium target that as we have estimated opens a new frontier in constraining the neutrino magnetic moment.

The discussed in the second part of the talk new results include two new effects that can be summarized as follows:

1) it is shown [20] that neutrino spin and spin-flavor oscillations can be engendered by weak interactions of neutrinos with the medium in the case when there are the transversal matter currents; different possibilities for the resonance amplification of oscillations are discussed, the neutrino Standard Model and non-standard interactions are accounted for;

2) within a new treatment [21] of the neutrino flavor, spin and spin-flavour oscillations in the presence of a constant magnetic field, that is based on the use of the exact neutrino stationary states in the magnetic field, it is shown that there is an interplay of neutrino oscillations on different frequencies. iIn particular: a) the amplitude of the flavour oscillations νLe↔ νLμ at the vacuum frequency is modulated by the magnetic field frequency μB , and b) the neutrino spin oscillation probability (without change of the neutrino flavour) exhibits the dependence on the neutrino energy and mass square difference Δm2 .

The discovered new phenomena in neutrino oscillations should be accounted for reinterpretation of results of already performed experiments on detection of astrophysical neutrino fluxes produced in astrophysical environments with strong magnetic fields and dense matter. These new neutrino oscillation phenomena are also of interest in view of future experiments on observations of supernova neutrino fluxes with large volume detectors like DUNE, JUNO and Hyper-Kamiokande.

Two other new results discussed in the concluding part of the talk are as follows:

3) a new theoretical framework, based on the quantum field theory of open systems applied to neutrinos, has been developed [23] to describe the neutrino evolution in external environments accounting for the effect of the neutrino quantum decoherence; we have used this approach to consider a new mechanism of the neutrino quantum decoherence engendered by the neutrino radiative decay to photons and dark photons in an astrophysical environment, the corresponding new constraints on the decoherence parameter have been obtained;

4) in [24] we have proposed an experimental setup to observe coherent elastic neutrino-atom scattering (CEνAS) using electron antineutrinos from tritium decay and a liquid helium target and shown that the sensitivity of this apparatus (when using 60 g of tritium) to a possible electron neutrino magnetic moment can be of order about 7×10−13μB at 90% C.L., that is more than one order of magnitude smaller than the current experimental limit.

The best world experimental bounds on neutrino electromagnetic properties are confronted with the predictions of theories beyond the Standard Model. It is shown that studies of neutrino electromagnetic properties provide a powerful tool to probe physics beyond the Standard Model.

References:

[1] C. Guinti and A. Studenikin, Neutrino electromagnetic interactions: A window to new physics, Rev. Mod. Phys. 87 (2015) 531-591.

[2] C. Giunti, K. Kouzakov, Y. F. Li, A. Lokhov, A. Studenikin, S. Zhou, Electromagnetic neutrinos in laboratory experiments and astrophysics, Annalen Phys. 528 (2016) 198.

[3] A. Studenikin, Neutrino electromagnetic interactions: A window to new physics - II,
PoS EPS-HEP2017 (2017) 137.

[4] A. Studenikin, Electromagnetic neutrino properties: new constraints and new effects,
PoS ICHEP2020 (2021)180.

[5] A. Beda, V. Brudanin, V. Egorov et al., The results of search for the neutrino magnetic
moment in GEMMA experiment , Adv. High Energy Phys. 2012 (2012) 350150.

[6] M. Agostini et al (Borexino coll.), Limiting neutrino magnetic moments with Borexino Phase-II solar neutrino data, Phys. Rev. D 96 (2017) 091103.

[7] A. Studenikin, New bounds on neutrino electric millicharge from limits on neutrino magnetic moment, Europhys. Lett. 107 (2014) 21001.

[8] D. Papoulias, T. Kosmas, COHERENT constraints to conventional and exotic neutrino physics, Phys. Rev. D 97 (2018) 033003.

[9] M. Cadeddu, C. Giunti, K. Kouzakov, Y.F. Li, A. Studenikin, Y.Y. Zhang, “Neutrino charge radii from COHERENT elastic neutrino-nucleus scattering”, Phys. Rev. D 98 (2018) 113010.

[10] N. Viaux, M. Catelan, P. B. Stetson, G. G. Raffelt et al., Particle-physics constraints from the globular cluster M5: neutrino dipole moments, Astron. & Astrophys. 558 (2013) A12.

[11] S. Arceo-Díaz, K.-P. Schröder, K. Zuber and D. Jack, Constraint on the magnetic dipole moment of neutrinos by the tip-RGB luminosity in ω-Centauri, Astropart. Phys. 70 (2015) 1.

[12] A. Studenikin, I. Tokarev, Millicharged neutrino with anomalous magnetic moment in rotating magnetized matter, Nucl. Phys. B 884 (2014) 396-407.

[13] O. G. Miranda, D. K. Papoulias, M. Tórtola, J. W. F. Valle, XENON1T signal from transition neutrino magnetic moments , Phys.Lett. B 808 (2020) 135685.

[14] E. Aprile et al. [XENON], Observation of excess electronic recoil Events in XENON1T, Phys. Rev. D 102 (2020) 072004.

[15] K. Babu, S. Jana, M. Lindner, Large neutrino magnetic moments in the light of recent experiments, JHEP 2010 (2020) 040.

[16] V. Brdar, A. Greljo, J. Kopp, T. Opferkuch, The neutrino magnetic moment portal: Cosmology, astrophysics, and direct detection, JCAP01 (2021) 039.

[17] A. Parada, Constraints on neutrino electric millicharge from experiments of elastic neutrino-electron interaction and future experimental proposals involving coherent elastic neutrino-nucleus scattering, Adv.High Energy Phys. 2020 (2020) 5908904.

[18] K. Kouzakov, A. Studenikin, Electromagnetic properties of massive neutrinos in low-energy
elastic neutrino-electron scattering, Phys. Rev. D 95 (2017) 055013.

[19] A. Grigoriev, A. Lokhov, A. Studenikin, A. Ternov, Spin light of neutrino in astrophysical environments, JCAP 1711 (2017) 024 (23 p.).

[20] P. Pustoshny, A. Studenikin, Neutrino spin and spin-flavour oscillations in transversal
matter currents with standard and non-standard interactions, Phys. Rev. D 98 (2018) 113009.

[21] A. Popov, A. Studenikin, Neutrino eigenstates and flavour, spin and spin-flavour oscillations in a constant magnetic field, Eur. Phys. J. C 79 (2019) 144.

[22] P. Kurashvili, K. Kouzakov, L. Chotorlishvili, A. Studenikin, Spin-flavor oscillations of ultrahigh-energy cosmic neutrinos in interstellar space: The role of neutrino magnetic moments”, Phys. Rev. D 96 (2017) 103017.

[23] K. Stankevich, A. Studenikin, Neutrino quantum decoherence engendered by neutrino radiative decay, Phys. Rev. D 101 (2020) 056004.

[24] M. Cadeddu, F. Dordei, C. Giunti, K. Kouzakov, E. Picciau, A. Studenikin, Potentialities of a low-energy detector based on 4He evaporation to observe atomic effects in coherent neutrino scattering and physics perspectives, Phys. Rev. D 100 (2019) 073014.

Speaker: Alexander Studenikin (Moscow State University and JINR)

Studenikin_26_07_2021_EPS_HEP.pdf

18 Distinguishing Dirac vs Majorana Neutrinos at CE$\nu$NS experiments

Coherent Elastic Neutrino Nucleus Scattering (CE$\nu$NS) provide a novel window to probe new physics connected with the well established non-vanishing neutrino masses. In this talk we will discuss how in the presence of a transition magnetic moment of neutrinos the CE$\nu$NS experiments have the potential to shed light on the nature of neutrinos: Dirac vs Majorana. In particular, we will take the NUCLEUS experiment as an example to demonstrate that through a study of differential energy distribution of the final states the CEνNS experiments can potentially achieve such a feat.

Speaker: Chandan Hati (Technische Universität München, James-Franck-Straße 1, D-85748 Garching, Germany)

CH_CEvNS_EPS_2021.pdf

T05: Heavy Ion Physics: Part 1

Note: All contributions are given 12 minutes + 3 min for questions

19 Recent heavy-flavor measurements with the ATLAS detector

Measurements of open heavy-flavor hadron production in heavy-ion collisions provide a powerful tool to study both initial-state effects on heavy-quark production and final-state interactions between heavy-quarks and the quark-gluon plasma (QGP). These measurements are performed with the ATLAS detector at the LHC and capitalize on the large statistics of the Run 2 Pb+Pb dataset. This talk presents published results on the azimuthal anisotropy ($v_2$ and $v_3$) of muons from heavy-flavor decays in Pb+Pb collisions, as well as new results on the nuclear modification factor ($R_\mathrm{AA}$) for heavy-flavor muons, both in the region $p_\mathrm{T} > 4$ GeV. In both measurements, muons from charm and bottom hadrons are statistically separated using the transverse impact parameter with respect to the primary collision vertex. Muons from both charm and bottom hadrons are found to have significant azimuthal anisotropies in Pb+Pb collisions, with larger anisotropies for muons from charm hadrons than for muons from bottom hadrons. Muons from both sources are also observed to be strongly suppressed with respect to the $pp$ baseline, in a way that depends on the mass of the parent hadron at low to moderate muon $p_\mathrm{T}$. The simultaneous measurement of multiple observables ($v_2$, $v_3$, and $R_\mathrm{AA}$) for both charm and bottom with the same detector and technique is particularly crucial in providing constraints on state of the art theoretical predictions.

Speaker: Jamie Nagle

nagle_atlas_heavyflavor_epshep2021.pdf

nagle_atlas_heavyflavor_epshep2021.pptx

20 Recent results of D0 mesons azimuthal anisotropy using the CMS detector

In a relativistic heavy ion collision, heavy flavor (charm and bottom) quarks are mostly created via hard processes at the early stage of collisions. We present the latest results of the azimuthal anisotropy coefficients v_n for prompt and non-prompt D0 mesons in PbPb, pPb, and pp collisions from the CMS experiment. The studies are about collectivity phenomena in smaller systems (pp and pPb), searches for the effects of very strong electromagnetic fields created in the initial stages of ultrarelativistic PbPb collisions, and charm quark energy loss in the quark-gluon plasma.

Speaker: Cesar Bernardes (Universidade Federal do Rio Grande do Sul)

talk_EPSHEP2021_CesarABernardes.pdf

21 Open charm and beauty production and anisotropy from small to large systems with ALICE

In this talk, the nuclear modification factor ($R_{\rm AA}$) and the elliptic flow ($v_{2}$) of open heavy-flavour hadrons via their hadronic and semileptonic decays to electrons at midrapidity and to muons at forward rapidity in heavy-ion collisions will be discussed. In particular, the latest results on the centrality dependence of $R_{\rm AA}$ of charmed hadrons, beauty-decay electrons, non-prompt $\mathrm{D}^0$ and the new measurement of non-prompt $\mathrm{D}^{+}_{s}$ in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV will be shown. They provide important constraints to the energy loss mechanisms in the medium and their mass dependence, and provide information about the fragmentation of heavy quarks to strange heavy-flavour hadrons. Final and high precision measurements of elliptic flow of heavy-flavour particles provide stringent information about the thermal degrees of freedom of heavy quarks in the QGP, path-length dependence of heavy-quark in-medium energy loss and recombination effects. The elliptic flow of charmed hadrons and of the beauty-decay electrons will help test whether heavy quarks thermalise in the medium. Comparisons with model calculations including the interaction of heavy quarks with the hot, dense, and deconfined medium will be discussed. In this contribution, the final measurements of beauty production using beauty-decay electrons and non-prompt D in pp collisions at $\sqrt{s}$ = 5.02 TeV are also reported. They provide important tests of perturbative QCD calculations.

Speaker: Stefano Trogolo (CERN)

Trogolo_EPSHEP_2021_Final.pdf

22 Recent LHCb results on charm in the QCD medium

With full particle ID, precision tracking, and calorimetry, the LHCb detector is able to measure prompt and non-prompt charm production through a variety of decay channels at forward rapidity. These unique abilities allow LHCb to study a wide range of exotic and conventional open and hidden charm states and their interactions in the QCD medium. Here we will discuss recent LHCb results on charm production in pp and pPb collisions, including the first results on chi_c production in nuclear collisions at the LHC, and compare the results with various theoretical models.

Speaker: Chenxi Gu (cern)

Recent LHCb results on charm in the QCD medium.pdf

23 Measurements of jet suppression and modification in heavy-ion collisions with ATLAS

Measurements of jet suppression and modification in heavy-ion collisions provide powerful and broad information on the dynamics of the hot, dense plasma formed in relativistic nucleus-nucleus collisions. In this talk we present measurements of jet energy loss and modification which are performed using the high-statistics Pb+Pb collision data at 5.02 TeV recorded during 2018 with the ATLAS detector at the LHC. These data can provide insight into the path length or system size dependence of energy loss, fluctuations in the energy loss process, the modification of parton fragmentation, and the re-distribution of lost energy.

This talk will first present a broad measurement of the single jet yields as a function of the azimuthal angle with respect to the 2nd, 3rd, and 4th event planes in Pb+Pb collisions. The azimuthal anisotropies for jets are reported as a function of jet $p_{\rm T}$ and centrality. This talk will also present a measurement of the fully unfolded dijet momentum balance in high-statistics Pb+Pb and pp data. The balance distributions are presented as a function of centrality and leading jet $p_{\rm T}$, exploring a significantly higher kinematic range than Run 1 results. Finally, the talk presents a measurement of Z-tagged charged hadron yields, which feature an opportunity to understand the energy loss, and its redistribution by the medium, for low-$p_{\rm T}$ partons in a calibrated way.

Speaker: Christopher McGinn (ATLAS, sPHENIX, University of Colorado Boulder)

cfm_EPSATLASHIJet_20210726.pdf

24 Influence of scattering versus coherent parton branching on the $k_T$ broadening of QCD cascades in a medium

Heavy ion collisions at high energies can be used as an interesting way to recreate and study the medium of the quark-gluon plasma (QGP).
We particularly investigate how jets produced in hard binary collisions evolve within a tentative medium and in particular how the jet-particle momentum components $k_T$ orthogonal to the jet
axis are affected.
We evolved the jets within a medium that contains both, transverse kicks
as well as medium induced coherent radiation within the MINCAS-algorithm [1] following the works of [2,3].
In this framework parton branching occurs simultaneously to scatterings within the medium, leading to the interference effects that reproduce the well known BDMPS-Z emission rates and sizeable $k_T$ broadening.
It is, thus, interesting to study the relative importances of $k_T$ broadening from the coherent splittings and different types of in-medium scatterings.
We find a clear hierarchy of the influences from different scattering effects and deflections during branchings:
While scattering still yields the largest contributions to broadening, the branching effects are comparable in size.
We also observed that the $k_T$ distributions in our results differ considerably from a Gaussian distribution in transverse momentum.

References:
[1] K. Kutak, W. Płaczek, R. Straka, Eur.Phys.J. C79 (2019) no.4, 317
[2] J.-P. Blaizot, F. Dominguez, E. Iancu, Y. Mehtar-Tani, JHEP 1301 (2013) 143
[3] J.-P. Blaizot, F. Dominguez, E. Iancu, Y. Mehtar-Tani, JHEP 1406 (2014) 075

Speaker: Martin Rohrmoser (Institute of Nuclear Physics, Polish Academy of Sciences)

eps-hep.pdf

25 Measurements of jet quenching via hadron+jet correlations in Pb-Pb and high-particle multiplicity pp collisions with ALICE

Interactions of high-$p_{T}$ partons with quark-gluon plasma (QGP) result in jet quenching, which is manifest by the suppression of high-$p_{T}$ jet yields and the modification of jet substructure and di-jet acoplanarity distributions.
Several jet quenching phenomena can be measured precisely over a wide range of jet $p_{T}$ using semi-inclusive distributions of charged-particle jets recoiling from a high-$p_{T}$ trigger hadron, which incorporate data-driven suppression of the large uncorrelated background produced in heavy-ion collisions.

In this talk we report semi-inclusive measurements of hadron-jet acoplanarity in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}} = 5.02$ TeV and high-particle multiplicity pp collisions at $\sqrt{s} = 13$ TeV. In the Pb-Pb system, where QGP formation is established, narrowing of the acoplanarity is observed relative to a reference distribution from pp collisions. In contrast, pp events with high-particle multiplicity exhibit a broadening of the acoplanarity relative to minimum bias events. In this case, however, qualitatively similar features are also seen in pp collisions generated by PYTHIA, which does not include jet quenching or other QGP effects. We will discuss the current status of these analyses, and prospects to understand the origin of these striking phenomena.

Speaker: Artem Kotliarov

Talk_EPS_2021_Kotliarov.pdf

26 First steps towards the quantum simulation of jet quenching

The leading order $\alpha_s$ effect in jet quenching corresponds to the broadening of the jet's transverse momentum, due to the multiple interactions with the underlying medium. A complete understanding of momentum broadening is critical for the success of jet quenching phenomenology.

In this talk, we introduce a strategy to quantum simulate single particle momentum broadening in a QCD background medium. We argue that it is, in principle, possible to extract the jet quenching parameter $\hat{q}$ from such an algorithm. More importantly, this corresponds to the first step towards simulating full medium induced parton showers, which is far beyond the capabilities of classical computers.

Speaker: Joao Barata (IGFAE)

Slides_Barata.pdf

T06: QCD and Hadronic Physics: Part 1: Exclusive physics and diffraction

Note: All contributions are given 12 minutes + 3 min for questions

Conveners: Ferenc Siklér (Wigner RCP, Budapest), Mateusz Dyndal (AGH UST Krakow)

27 Measurement of Exclusive pi+pi- and rho0 Meson Photoproduction at HERA

Exclusive photoproduction of $\rho^0(770)$ mesons is studied using the H1 detector at the $ep$ collider HERA. A sample of about 900000 events is used to measure single- and double-differential cross sections for the reaction $\gamma{}p\to \pi^{+}\pi^{-}Y$. Reactions where the proton stays intact ($m_Y=m_p$) are statistically separated from those where the proton dissociates to a low-mass hadronic system ($m_p<{}m_Y<{}10$ GeV). The double-differential cross sections are measured as a function of the invariant mass $m_{\pi\pi}$ of the decay pions and the squared $4$-momentum transfer $t$ at the proton vertex. The measurements are presented in various bins of the photon-proton collision energy $W_{\gamma{}p}$. The phase space restrictions are $0.5<{}m_{\pi\pi}<{}2.2$ GeV, $\vert{}t\vert<{}1.5$ GeV$^2$, and $20<{}W_{\gamma{}p}<{}80$ GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the $m_{\pi\pi}$ dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the $\rho^0(770)$ meson mass and width at $m_\rho=770.8^{+2.6}_{-2.7}$ (tot) MeV and $\Gamma_\rho=151.3^{+2.7}_{-3.6}$v (tot) MeV, respectively. The model is used to extract the $\rho^0(770)$ contribution to the $\pi^{+}\pi^{-}$ cross sections and measure it as a function of $t$ and $W_{\gamma{}p}$. In a Regge asymptotic limit in which one Regge trajectory $\alpha(t)$ dominates, the intercept $\alpha(t{=}0)=1.0654^{+0.0098}_{-0.0067}$ (tot) and the slope $\alpha^\prime(t{=}0)=0.233^{+0.067}_{-0.074}$ (tot) GeV$^{-2}$ of the $t$ dependence are extracted for the case $m_Y{=}m_p$.

Eur.Phys.J.C80 (2020), 1189

Speaker: Arthur Bolz (BELLE (BELLE Gruppe))

2021_EPS_RhoPhotoAtH1.pdf

28 Central exclusive production of pipi, KK and pp pairs with forward proton measured in Roman Pot detectors in proton proton collisions at sqrt(s)=200 GeV with the STAR detector.

Abstract attached as pdf file.

Speaker: Leszek Adamczyk (AGH University of Science and Technology (PL))

EPS_2021.pdf

29 Production of dileptons via photon-photon fusion in proton-proton collisions with one forward proton measurement

We discuss mechanisms of dilepton production in proton-proton collisions with rapidity gap in the main detector and one forward proton in the forward proton detectors. This is relevant for LHC measurements by ATLAS+AFP and CMS+PPS. Transverse momenta of the intermediate photons are included and photon fluxes are expressed in terms of proton electromagnetic form factors and structure functions. Differential distributions in $\xi_{1/2}$, $M_{ll}$, $Y_{ll}$, $p_{t,ll}$ are shown and the competition of different mechanisms is discussed. Both double-elastic and single-dissociative processes are included in the calculation. We discuss also mechanism with one forward $\Delta^+$ isobar, or other proton resonances in the final state not discussed so far in the literature. The role of several cuts is studied. The rapidity gap survival factor is calculated for each contribution separately. The soft rapidity gap survival factor for the case of single proton measurement is significantly smaller than that for the inclusive case (no proton measurement). The gap survival with and without proton measurement in forward proton detector are compared and the underlying dynamics is discussed. The dependence on the parametrization of the proton structure functions is shown in addition. The gap survival factor for the single-dissociative mechanism due to minijet emission into the main detector are calculated in addition. The corresponding gap survival factor depends on the invariant mass of the dilepton system as well as the mass of the proton remnant and rapidity of the lepton pair.

A. Szczurek, B. Linek and M. {\L}uszczak, a paper in preparation.

Speaker: Marta Luszczak (University of Rzeszow)

szczurek_pp_llp.pdf

30 Measurements of diffractive physics and soft QCD at ATLAS

In this talk we present various measurements of diffractive physics and soft QCD processes performed using data collected by the ATLAS experiment at the LHC. Single diffractive processes (pp->pX) are studied reconstructing the particles from the dissociative system (X) with the ATLAS detector, while the intact proton is reconstructed and measured in a forward detector. If available, this talk will also present the underlying event measurements using strange particles as probes. Also in this talk, we present, If available, studies of correlation phenomena in order to study the dynamics of hadronization formation.

Speaker: Dr Lydia Beresford (CERN)

Beresford_EPS_July21.pdf

31 Single-diffractive production of heavy mesons in pp and pA collisions

In this talk we present our theoretical results for the single-diffractive production of open heavy flavor mesons and non-prompt charmonia in pp and pA collisions. Using the color dipole framework, we found that this mechanism constitutes 0.5-2 per cent of the inclusive production of the same mesons. In Tevatron kinematics our theoretical results are in reasonable agreement with the available experimental data. In LHC kinematics we found that the cross-section is sufficiently large and could be accessed experimentally. We also analyzed the dependence on multiplicity of co-produced hadrons and found that it should be significantly slower than that of inclusive production of the same heavy mesons. If this expectation will be confirmed experimentally, this could constitute important contribution to our understanding of multiplicity enhancement mechanisms in the production of different quarkonia states. We also analyzed this process in pA collisions and found that the cross-section per nucleon decerases by up to a factor of two compared to pp production due to nuclear saturation effects.

This presentation is partially based on our recent publication Phys.Rev.D 102 (2020) 7, 076020 [arXiv:2008.12446 [hep-ph]]

Speaker: Dr Marat Siddikov (Federico Santa Maria Technical University (UTFSM))

Talk_EPSHEP2021_SD3a.pdf

32 Searching for the odderon in exclusive $pp \to pp \phi$ and $pp \to pp \phi \phi$ reactions at the LHC

We discuss the possibility to use the exclusive $pp \to pp \phi$ and $pp \to pp \phi \phi$ reactions in identifying the odderon exchange, the charge conjugation C = -1 counterpart of the C = +1 pomeron. The odderon was introduced on theoretical grounds in [1]. Results of the TOTEM collaboration suggest that the odderon exchange can be responsible for a disagreement of theoretical calculations and the TOTEM data [2,3]. It is premature to draw definite conclusion. Here we present some recent studies for two related processes where the odderon exchange may show up. We apply recently proposed the tensor-pomeron and vector-odderon model [4]. The first reaction is central exclusive production (CEP) of pairs of $\phi$ mesons [5]. Here odderon exchange is not excluded by the WA102 experimental data [7] for high $\phi \phi$ invariant masses. The process is advantageous as here odderon does not couple to protons. Comparison with data from the WA102 experiment and predictions for the LHC experiments will be presented. The observation of large $M_{\phi \phi}$ and $Y_{\phi \phi}$ (rapidity distance between the $\phi$) seems well suited to identify odderon exchange. We discuss also the $p p \to p p \phi$ reaction [6]. At high energies probably the photon-pomeron fusion is the dominant process. The odderon-pomeron fusion is an interesting alternative. Adding odderon exchange with parameters adjusted for the $\phi \phi$ production improves considerably description of the proton-proton angular correlations measured by the WA102 collaboration [8]. At the low energy we consider also some other subleading processes that turned out to be rather small. A combined analysis of both the $K^+ K^-$ and $\mu^+ \mu^-$ channels should be the ultimate goal in searches for odderon in single $\phi$ CEP at the LHC. Predictions for the LHC experiments will be presented.

[1] L. Łukaszuk, B. Nicolescu, Lett. Nuovo Cim. 8 (1973) 405;
[2] E. Martynov, B. Nicolescu, Phys. Lett. B786 (2018) 207;
[3] TOTEM Collaboration, Eur. Phys. J. C79 (2019) 785, Eur. Phys. J. C80 (2020) 91;
[4] C. Ewerz, M. Maniatis, O. Nachtmann, Annals Phys. 342 (2014) 31;
[5] P. Lebiedowicz, O. Nachtmann, A. Szczurek, Phys. Rev. D99 (2019) 094034;
[6] P. Lebiedowicz, O. Nachtmann, A. Szczurek, Phys. Rev. D101 (2020) 094012;
[7] WA102 Collaboration, Phys. Lett. B432 (1998) 436;
[8] A. Kirk, Phys. Lett. B489 (2000) 29.

Speaker: Piotr Lebiedowicz (IFJ PAN, Cracow)

EPS-HEP_2021_Lebiedowicz.pdf

33 Comparison of $pp$ and $p \bar{p}$ differential elastic cross sections and observation of the exchange of a colorless $C$-odd gluonic compound

We describe an analysis comparing the $p\bar{p}$ elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96~TeV to that in $pp$ collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of $\sqrt{s} =$ 1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the $pp$ cross section.
The two data sets disagree at the 3.4$\sigma$ level and thus provide evidence for the $t$-channel exchange of a colorless, $C$-odd gluonic compound, also known as the odderon.
We combine these results with a TOTEM analysis of the same $C$-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in $pp$ scattering.
The combined significance is larger than 5$\sigma$ and is interpreted as the first observation of the exchange of a colorless, $C$-odd gluonic compound.

Speaker: Christophe Royon (The University of Kansas (US))

eps2021.pdf

T07: Top and Electroweak Physics: Part 1

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Elisabetta Gallo-Voss (CMS (CMS-Experiment)), William Barter (Imperial College London)

34 Measurements of W and Z boson production at ATLAS

Precision measurements of the production cross-sections of W/Z boson at LHC provide important tests of perturbative QCD and information about the parton distribution functions for quarks within the proton. We present measurements of the transverse momentum distribution of the vector boson at 13 TeV. If available differential measurements in the side band of the Z-mass peak are also presented. The measurements are corrected for detector inefficiency and resolution and compared with state-of-the-art theoretical calculations.

Speaker: Matthias Schott (Uni Mainz)

EPS2021_WZ_MSchott.pdf

35 CMS Inclusive vector bosons results including Drell-Yan measurements in a wide mass range

Recent inclusive W,Z measurements and differential results on DY dilepton productions in a wide range of invariant masses are presented, making use of CMS proton collision data at 13 TeV.

Speaker: Louis Moureaux (Université Libre de Bruxelles)

Moureaux_SMPV_EPS2021_v3.pdf

36 Measurement of the W boson mass at LHCb

The LHCb experiment covers the forward region of proton-proton collisions, and it can improve the current electroweak landscape by studying the production of W and Z boson in this phase space complementary to ATLAS and CMS. Several preliminary studies have shown the potential of the LHCb experiment to measure the W boson mass with a muon pT based technique, which could yield a statistical precision of 10 MeV if using the full Run 2 dataset. A proof-of-concept measurement of the W boson mass, using only the 2016 dataset, will be presented.

Speaker: Ross Hunter (The University of Warwick, U.K.)

mW_EPS.pdf

37 Measuring the polarization of boosted, hadronic $W$ bosons with jet substructure observables

In this work, we present a new technique to measure the longitudinal and transverse polarization fractions of hadronic decays of boosted $W$ bosons. We introduce a new jet substructure observable denoted as $p_\theta$, which is a proxy for the parton level decay polar angle of the $W$ boson in its rest frame. We show that the distribution of this observable is sensitive to the polarization of $W$ bosons and can therefore be used to reconstruct the $W$ polarization in a model-independent way. As a test case, we study the efficacy of our technique on vector boson scattering processes at the high luminosity Large Hadron Collider and we find that our technique can determine the longitudinal polarization fraction to within $\pm 0.15$.

Speaker: Songshaptak De (IIT Bombay)

EPSHEP21_SDe.pdf

38 Experimental challenges towards a full exploitation of the FCC-ee potential

The European Strategy for Particle Physics ESPP has recommended a financial and technical feasibility of the FCC colliders and their infrastructure to be carried out for its next upgrade around 2025/6. The integral FCC program combines in the same 100km infrastructure a high luminosity Higgs and Electroweak factory e+e- collider, FCC-ee, followed by a 100 TeV hadron collider. With its high luminosity, its clean experimental conditions, and a range of energies that cover the four heaviest particles known today, FCC-ee offers a wealth of physics possibilities, with high potential for discoveries. It is an essential and complementary step towards the 100 TeV hadron collider, and the whole combined program is uniquely rich and powerful. This vision is the backbone of the 2020 ESPP.
The main challenges of the study are now to design the detector systems that can, demonstrably, fully exploit its potential, while being technically feasible and affordable on the project time scale (start of operations around 2040). With 5.1012 Z produced, the TeraZ run offers b,c,  and QCD physics opportunities, as well as ppm precision challenges on electroweak precision observables and unique searches for extremely rare processes. This breath of opportunities requires very varied and quite specific detector requirements, compared with the higher energy program on Higgs and top physics which is more comparable to the linear collider detector optimization. This variety is clearly in favour of a collider design which foresees four experimental interaction regions. The high precision and varied program is also a considerable challenge for precision calculations.
The opportunities will be reviewed and the most striking detector challenges will be highlighted.

Speaker: Alain Blondel (Universite de Geneve (CH) and CNRS (France))

ABlondel-FCC-ee-challenges-2021-07-26-EPS-HEP.pptx

39 Electroweak Precision Physics at FCC-ee

The Future Circular Collider with electron-positron beams (FCC-ee) should provide improvements of the electroweak precision measurement concerning Z, W, H, and their masses by a large factor over the present status. The unparalleled experimental precision would open, via Electroweak loop corrections, a broad discovery potential for new, at least weakly interacting particles up to high energy scales. The Z boson mass and width, as well as the Z to bb partial width, and the forward-backward asymmetries for leptons and quarks can be measured with high precision with the run at the Z pole, where the instantaneous luminosity is expected to be five to six orders of magnitude larger than LEP. As a result, a precise determination of the effective weak mixing angle, as well as of the running electromagnetic coupling can be extracted directly from the data. Considerable improvements of the strong coupling constant determination will be possible with the measurements of the hadronic widths of the Z and W bosons.

Speaker: Jan Eysermans (MIT)

Eysermans_EWKPhysics_EPS_26072021.pdf

40 Vector boson associated with heavy-flavor jets in CMS

The associated production of vector bosons and jets originating from heavy-flavour (c or b) quarks is a large background source in measurements of other standard model processes, Higgs boson studies, and many searches for physics beyond the standard model. The study of events with a vector boson accompanied by heavy-flavour jets is crucial to refine the theoretical calculations in perturbative QCD, as well as to validate associated Monte Carlo predictions. Differential cross sections are measured as a function of several kinematic observables with the CMS detector.

Speaker: Sergio Sanchez Navas

EPS2021.pdf

41 Two-loop QCD corrections to Wbb production at hadron colliders

I will present an analytic computation of the two-loop QCD corrections to ud->Wbb process for an on-shell W-boson using the leading colour and massless bottom quark approximations. The computation involves integration-by-parts reduction of the unpolarised squared matrix element using finite field reconstruction techniques and identifying an independent basis of special functions that allows an analytic subtraction of the infrared and ultraviolet poles.

Speaker: Heribertus Bayu Hartanto (University of Cambridge)

Bayu_EPSHEP2021.pdf

T08: Flavour Physics and CP Violation: Part 1

Conveners: Jorge Martin Camalich (Instituto de Astrofisica de Canarias), Shikma Bressler (Weizmann Institute of Science)

42 QCD factorization tests with $\bar{B^0} \to D^{(*)+}\pi^-$ and $\bar{B^0} \to D^{(*)+}K^-$ decays at Belle

We report new results of the branching fractions $\mathcal{B}(\bar{B}^0\to D^{*+}\pi^{-})$ and $\mathcal{B}(\bar{B}^0\to D^{*+}K^{-})$ measured using $772\times 10^{6}$ $B$-meson pairs recorded by the Belle experiment. The ratio of the branching fractions is measured in a way that allows for the cancellation of systematic uncertainties arising from the $D$-meson reconstruction. Furthermore, we report a new high-precision test of QCD factorisation by measuring ratios of $\bar{B}^0\to D^{*+}h^{-}$ $(h=\pi,K)$ and $\bar{B}^0\to D^{*+}\ell^{-}\bar{\nu}_{\ell}$ decays at fixed momentum transfers for different particle species. The talk also covers related measurements of $B \to D h$ decays performed with the full Belle data.

Speaker: Eiasha Waheed (High Energy Accelerator Research Organization (KEK))

EPS_2021_EiashaWaheed.pdf

43 Measurement of the mixing parameter $\chi_d$ in semi-leptonic B meson decays at Belle II

Inclusive semi-leptonic decays of $B$ mesons are an excellent avenue for the study of B\bar{B} mixing, given their large branching fraction. In this talk, we present the measurement of the time integrated mixing parameter, $\chi_d$, using data collected by the Belle II detector. The Belle II experiment is located at the SuperKEKB laboratory in Tsukuba, Japan where electron-positron collisions at the $\Upsilon(4S)$ energy yield a large number of B\bar{B} events. The mixing parameter $\chi_d$ is determined by examining the charge of reconstructed lepton pairs in $B \rightarrow X \ell \nu$ events. The result is based on 74 $fb^{-1}$ of Belle II reprocessed data.

Speaker: Stephan Duell (BELLE (BELLE II Experiment))

Duell_EPSHEP_260721.pdf

44 CP-Violating Invariants in the SMEFT

In the Standard Model, CP violation in the Electroweak sector is parametrized by the Jarlskog Invariant. This is the flavor invariant sensitive to CP violation with the least number of Yukawa matrices that can be built. When higher dimensional operators are allowed, and the Standard Model Effective Field Theory is constructed, numerous new sources for CP violation can appear. However, the description of CP violation as a collective effect, present in the SM, is inherited by its Effective extension. Here, I will discuss how such a behaviour can be consistently captured, at dimension 6, by flavor invariant, CP violating objects, linear in the Wilson coefficients. Such a description ensures that CP violation in the SMEFT is treated in a basis independent manner. In particular, I claim these are the objects that have to vanish, together with the SM Jarlskog Invariant, for CP to be conserved, and viceversa. The scaling properties of these invariants demonstrates that, while CP is not an accidental symmetry of the Standard Model, its breaking is accidentally small at the renormalizable level. Implications for specific flavor models, such as MFV, will be addressed.

Speaker: Emanuele Gendy (UNI/TH (Uni Hamburg, Institut fuer Theoretische Physik))

EPS.pdf

45 Unitarity Triangle global fits testing the Standard Model: UTfit 2021 SM update

Flavour physics represents a unique test bench for the Standard Model (SM). New analyses performed at the LHC experiments are now providing unprecedented insights into CKM metrology and new results for rare decays. The CKM picture can provide very precise SM predictions through global analyses.
We present here the results of the latest global SM analysis performed by the UTfit collaboration including all the most updated inputs from experiments, lattice QCD and phenomenological calculations.
We update our analysis of D meson mixing including the latest experimental results. We also derive constraints on absorptive and dispersive CP violation by combining all available data, and discuss future projections. We also provide posterior distributions for observable parameters appearing in D physics.
Finally we present the perspectives for future UT analyses on the basis of existing extrapolations of experimental results from the Belle-II and LHCb experiments, as well as of expected improvements from Lattice QCD computations.

Speaker: Marcella Bona (Queen Mary University of London (UK))

bona-utfit.pdf

46 CP-violating axions

While the axion was originally introduced to "wash out" CP violation from strong interactions, new sources of CP violation beyond QCD (needed e.g. for the matter-antimatter asymmetry) might manifest themselves via a tiny scalar axion-nucleon component. The latter can be experimentally probed in axion-mediated force experiments, as suggested long ago by J.E. Moody and F. Wilczek. In the present contribution, I will review CP-violating axion searches and report on a recent calculation of the scalar axion-nucleon coupling based on chiral Lagrangian techniques.

Speaker: Luca Di Luzio (University of Padua and INFN)

Di_Luzio_EPS2021.pdf

47 Measurements of strong-phase parameters at BESIII

BESIII has collected 2.9 of e+e- collision data sample at 3.773 GeV. We report recent measurements of strong phase differences in D0 and D0-bar decays of KSpi+pi-, KSK+K-, K-pi+pi+pi- and K-pi+pi0. The obtained parameters are important to reduce the systematic uncertainty in the gamma/phi_3 measurement at LHCb and Belle II.

Speaker: Anita Lavania (IIT Madras)

EPS_V4.pdf

48 Measurements of the CKM angle gamma at LHCb

The tree-level determination of the CKM angle gamma is a standard candle measurement of CP violation in the Standard Model. The latest LHCb results from time-integrated measurements of CP violation using beauty to open charm decays are presented. A new combination of all LHCb measurements is also performed. A precision of four degrees is obtained, which dominates the world average.

Speaker: Dr Mark Whitehead (University of Bristol)

mwhitehe_eps_2021.pdf

T09: Higgs Physics: Precision - part 1

Conveners: meng xiao (zhejiang university), Sarah Heim (DESY), Michael Trott (NBI), Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris)

49 Measurements and interpretations of Simplified Template Cross Sections, differential and fiducial cross sections in Higgs boson decays to two photons with the ATLAS detector

Higgs boson decays to two photons can be selected with high efficiency, and the very good invariant mass resolution allows a robust subtraction of the backgrounds. This talk will present measurements of Simplified Template Cross Sections, differential and fiducial cross sections, as measured in the diphoton decay channel by the ATLAS detector using the full Run 2 dataset of pp collision data collected at 13 TeV at the LHC, and their respective interpretations in the context of an Effective Field Theory.

Speaker: Eleonora Rossi (LAPP)

ER_Hyy_EPS_2607.pdf

50 Measurements and interpretations of Simplified Template Cross Sections and differential and fiducial cross sections in Higgs boson decays to two W bosons with the ATLAS detector

The Higgs boson decay to two W bosons has the largest bosonic branching fraction and can be used to perform some of the most precise measurements of the Higgs boson production cross sections. This talk will present cross section measurements using pp collision data collected at 13 TeV, including those for the different Higgs boson production processes in the Simplified Template Cross Section framework.

Speaker: Yun-Ju Lu (National Tsing Hua University (TW))

EPS2021_HWW_Yun-Ju_Lu_210726.pdf

51 Measurements and interpretations of Simplified Template Cross Sections, differential and fiducial cross sections in Higgs boson decays to four leptons with the ATLAS detector

Higgs boson decays to four leptons can be selected with a very high purity and are very well suited for measurements of Higgs boson properties, despite the small H→ZZ→4l branching ratio. This talk will present measurements of differential cross sections, as well as cross section measurements for the different Higgs boson production processes in the Simplified Template Cross Section framework using pp collision data collected at 13 TeV.

Speaker: Christos Anastopoulos

EPS_2021.pdf

52 Measurements of Higgs boson cross sections and differential distributions in bosonic final states (CMS)

The latest results obtained with CMS data collected at a centre-of-mass energy of 13 TeV targeting Higgs boson decays into gammagamma, WW, ZZ final states at CMS will be discussed.

Speaker: Jonathon Langford (Imperial College (GB))

eps_jlangford.pdf

53 Parton-Shower Effects in Higgs Production via Vector-Boson Fusion

We present a systematic investigation of parton-shower and matching uncertainties of perturbative origin for Higgs-boson production via vector-boson fusion. To this end we employ different generators at next-to-leading order QCD accuracy matched with shower Monte Carlo programs, $\texttt{PYTHIA8}$, and $\texttt{HERWIG7}$, and a next-to-next-to-leading order QCD calculation.
We thoroughly analyse the intrinsic sources of uncertainty within each generator, and then compare predictions among the different tools using the respective recommended setups. Within typical vector-boson fusion cuts, the resulting uncertainties on observables that are accurate to next-to-leading order are at the $10\%$ level for rates and even smaller for shapes. For observables sensitive to extra radiation effects, uncertainties of about $20\%$ are found.
We furthermore show how a specific recoil scheme is needed when $\texttt{PYTHIA8}$ is employed, in order not to encounter unphysical enhancements for these observables.
We conclude that for vector-boson fusion processes an assessment of the uncertainties associated with an NLO+PS simulation at next-to-leading order matched to parton showers based only on the variation of renormalisation, factorisation and shower scales systematically underestimates their true size.

Speaker: Johannes Scheller (Eberhard Karls Universität Tübingen)

Talk_EPSHEP_Scheller_preliminary.pdf

54 Combined measurements of Higgs boson production and decays with the ATLAS detector

The most precise measurements of Higgs boson cross sections, using the framework of simplified template cross sections, are obtained from a combination of measurements performed in the different Higgs boson decay channels using pp collision data with a center-of-mass energy of 13 TeV. This talk presents the combined measurements, as well as their interpretations in terms of Higgs coupling modifiers and their ratios, also taking into account results of searches for H->invisible decays as well as off-shell Higgs boson production. It also presents interpretations in generic 2HDM models and in the hMSSM, and in the framework of an Effective Field Theory.

Speaker: Yanping Huang

2021_EPS_v4.pdf

55 Studies of the CP properties of the Higgs boson at the ATLAS experiment

Studies of the CP properties of the Higgs boson in various production modes and decay channels are presented. Limits on the mixing of CP-even and CP-odd Higgs states are set by exploiting the properties of diverse final states.

Speaker: William Leight (ATLAS (ATLAS Dark Matter with Higgs))

eps 2021.pdf

56 The JHU generator framework: EFT applications in Higgs physics

The JHUGenerator framework includes an event generator of all anomalous Higgs boson interactions in both production and decay and the MELA library for matrix element analyses. The framework also allows using dimension-six operators of an EFT in on-shell and off-shell production together with triple and quartic gauge boson interactions. One new feature is the JHUGenLexicon interface for relating the anomalous coupling formulation with popular EFT bases. Some of the new features are illustrated along with projections for experimental measurements with the full LHC and HL-LHC datasets.

Speaker: Jeffrey Davis (Johns Hopkins University )

EPS_JHUGen_Davis.pdf

57 GeoSMEFT and applications [until 12:09, just shortened for agenda purposes]

I will discuss the geometric formulation of the SMEFT and its applications.

Speaker: Tyler Corbett (NBI)

CorbettEPS2021.pdf

T10: Searches for New Physics: Part 1

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Cristina Botta (University of Zurich)

58 Searches for strong production of supersymmetric particles with the ATLAS detector

Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the gluons and third generation quarks with masses light enough to be produced at the LHC. This talk will present the latest results of searches conducted by the ATLAS experiment which target gluino and squark production, including stop and sbottom, in a variety of decay modes, focusing on decay modes in which R-parity is conserved and therefore the lightest SUSY particle is a stable dark matter candidate.

Speaker: Jonathan Long (Urbana UI)

EPS2021_Long.pdf

59 Searches for third generation SUSY particles with the CMS experiment

Several searches for supersymmetric partners of the top quark and tau lepton have been performed by the CMS Collaboration using the full dataset of proton-proton collisions collected during the Run 2 of the LHC at a center-of-mass energy of 13 TeV. The main features and results of these analyses will be presented.

Speaker: Giulia Collura (UCSB)

210726_EPS.pdf

60 Searches for electroweak production of supersymmetric particles with the ATLAS detector

The direct production of electroweak SUSY particles, including sleptons, charginos, and neutralinos, is a particularly interesting area of search at the LHC, as considerations on dark matter and the naturalness of the Higgs mass motivate the existence of light electroweakinos. The small production cross sections lead to difficult searches, despite relatively clean final states. This talk will highlight the most recent results of searches performed by the ATLAS experiment for supersymmetric particles produced via electroweak processes, including analyses targeting small mass splittings between SUSY particles, with a focus on searches that target models on which R-parity is conserved. Sophisticated analysis techniques, including machine learning, are employed to increase the sensitivity for these processes.

Speaker: Stefano Zambito (CERN)

Zambito_EPS-HEP2021.pdf

61 Search for electroweak SUSY production in leptonic and hadronic final states with the CMS experiment

Several searches for supersymmetry produced through electroweak processes have been performed by the CMS Collaboration using the full dataset of proton-proton collisions collected during the Run 2 of the LHC at a center-of-mass energy of 13 TeV. The main features and results of analyses that select events with leptonic and hadronic final states will be presented.

Speaker: Liam Wezenbeek (UGent/ULB)

EPS2021_EWKSUSY_LiamWezenbeek.pdf

62 Constraining challenging regions of the SUSY parameter space with the CMS experiment

Supersymmetric models are characterized by a strong diversity of experimental signatures. Since general-purpose searches have not yet given any clear indication of new physics, dedicated methodologies and tools have been developed to target the regions of the parameter space where the analysis is most challenging and SUSY might still lie undetected. This presentation will describe relevant examples among searches performed by the CMS Collaboration using the full dataset of proton-proton collisions collected during the Run 2 of the LHC at a center-of-mass energy of 13 TeV.

Speaker: Peter Eduard Meiring (Universitaet Zuerich (CH))

EPS-HEP21 P.E.Meiring Constraining Challenging regions of SUSY parameter space with CMS.pdf

63 Exploring the frontier of R-parity-violating supersymmetry with the ATLAS detector

Supersymmetry models in which R-parity violation occurs predict a wide range of experimental signatures at the LHC, including many high-multiplicity final states without large missing transverse momentum. These models are motivated by the hierarchy problem and for some parameters naturally explain the lightness of the standard model neutrinos. Searches for RPV SUSY signatures require dedicated signal regions and innovative techniques to estimate the challenging backgrounds. This talk will highlight the latest results of searches conducted by the ATLAS experiment which target supersymmetric particles produced via both strong and electroweak processes in R-parity violating scenarios.

Speaker: Michael Holzbock (Munich MPI)

EPS-2021-RPV-SUSY.pdf

64 New constraints on flavour violating supersymmetry

We present an update on the constraints on general MSSM scenarios with non-minimal sources of flavour violation (NMFV), including all theoretical constraints and the most recent experimental bounds.
Using an MCMC algorithm and the public code SuperIso, we compute various flavour observables and the muon $(g-2)$ and impose the LHC direct search limits.
We present an up-to-date calculation of the relevant observables, in particular those related to $b\to s ll$ transitions which manifest tensions with the SM predictions, and show the latest allowed NMFV parameter ranges, in light of the most recent experimental bounds.
We finally discuss and propose a few benchmark scenarios for future BSM searches.

Speaker: Mohamed Amine Boussejra (Lyon University)

Boussejra_NMFV.pdf

65 New constraints on supersymmetry using neutrino telescopes

We introduce a new approach to set limits on long-lived charged particles using neutrino telescopes and apply it to data. Towards the horizon, we expect a suppression of low-energy muons and electrons, due to the amount of material they must traverse, to reach the detector. Should the new long-lived charged particle possess a larger mass than the muon, then its energy loss will be suppressed compared to the latter. This results in them being able to reach underground neutrino detectors from the horizon, while appearing as minimally ionizing tracks. The only expected background are low-energy muons produced by neutrinos near the detector.
Using one year of public IceCube data this approach can set a lower mass bound of 320 GeV on the stau, which is predicted in some supersymmetric scenarios. Extending this methodology to ten years of data, we predict that IceCube can set a lower mass bound of 450 GeV, similar to current limits set by collider-based experiments. This opens the possibility of complimentary and competitive studies on new long-lived, charged particles using already existing and upcoming neutrino telescopes.

Speaker: Stephan Meighen-Berger (Technical University Munich)

EPS_HEP_New_Constraints_susy_neutrino_telescopes.pdf

T12: Detector R&D and Data Handling: LHC Run 3

Conveners: Magnus Mager (CERN), Vincent Boudry (LLR – École polytechnique)

66 Triggering in ATLAS in Run 2 and Run 3

The ATLAS experiment at the LHC can record about 1 kHz of physics collisions, out of an LHC design bunch crossing rate of 40 MHz. To achieve a high selection efficiency for rare physics events while reducing the significant background rate, a two-level trigger system is used.

The event selection is based on physics signatures, such as the presence of energetic leptons, photons, jets or missing energy. In addition, the trigger system can exploit algorithms using topological information and multivariate methods to carry out the filtering for the many physics analyses pursued by the ATLAS collaboration. In Run 2, around 1500 individual selection paths, the trigger chains, were used for data taking, each with specified rate and bandwidth assignments.

We will give an overview of the Run-2 trigger menu and its performance, allowing the audience to get a taste of the broad physics program that the trigger is supporting. We present the tools that allow us to predict and optimize the trigger rates and CPU consumption for the anticipated LHC luminosities and outline the system to monitor deviations from the individual trigger target rates, and to quickly react to the changing LHC conditions and data taking scenarios.
As an outlook to the upcoming ATLAS data-taking period in Run 3 from 2022 onwards, we present the design principles and ongoing implementation of the new trigger software within the multithreaded framework AthenaMT together with some outlook to the expected performance improvements.

Speaker: Yasuyuki Okumura (University of Tokyo (JP))

yasuyuki.okumura.20210726.02.pdf

67 CMS Tracker Alignment: Legacy results from LHC Run-II and Run-III prospects

The inner tracking system of the CMS experiment, which comprise of Silicon Pixel and Silicon Strip detectors, is designed to provide a precise measurement of the momentum of charged particles and to reconstruct the primary and secondary vertices. The movements of the different substructures of the tracker detectors driven by the operating conditions during data taking, require to regularly update the detector geometry in order to accurately describe position, orientation, and curvature of the tracker modules.

The procedure in which new parameters of the tracker geometry are determined is known as alignment of the tracker. The alignment procedure is performed several times during data taking using reconstructed tracks from collisions and cosmic rays data, and later on, further refined after the data taking period is finished. The tracker alignment performance corresponding to the ultimate accuracy of the alignment calibration for the legacy reprocessing of the CMS Run-II data will be presented. The data-driven methods used to derive the alignment parameters and the set of validations that monitor the performance of physics observables after the alignment will be reviewed. Finally, the prospects for the alignment calibration during the upcoming run of the LHC, where more challenging operation conditions are expected, will be addressed.

Speaker: Sandra Consuegra Rodriguez (CMS (CMS Fachgruppe HIGGS))

EPS-HEP2021_SandraConsuegraRodriguez.pdf

68 First results of the newly installed, MAPS based, ALICE Inner Tracking System

The ALICE Inner Tracking System (ITS) has recently been replaced with a full silicon-pixel detector constructed entirely with CMOS monolithic active pixel sensors. It consists of three inner layers (50 $\mu$m thick sensors) and four outer layers (100 $\mu$m thick sensors) covering 10 m$^2$ and containing 12.5 billion pixels with a pixel size of 27 $\mu$m x 29 $\mu$m. Its increased granularity, the very low material budget (0.35% X$_0$/layer in the inner barrel) as well as a small radius of the innermost layer combined with a thin beam pipe, will result in a significant improvement of impact-parameter resolution and tracking efficiency at low $p_{\rm T}$ with respect to the previous tracker. The assembly of the full detector and services finished in December 2019. A comprehensive commissioning phase (on surface) was completed in December 2020, including detector calibration, fake-hit rate determination, data transmission tests and preliminary evaluation of the detector efficiency and the sensors alignment, based on reconstruction of cosmic rays tracks. The commissioning of the ITS within the ALICE apparatus has recently started. After a first phase of standalone tests and detector performance optimization, the ITS will be included in the global commissioning activities in summer 2021. In this talk, the first results of the performance of the new ALICE ITS detector, studied during commissioning, will be presented.

Speaker: Jian Liu

EPS_Jian_Liu-20210726.pdf

69 ATLAS LAr Calorimeter Commissioning for LHC Run-3

Liquid argon (LAr) sampling calorimeters are employed by ATLAS for all electromagnetic calorimetry in the pseudo-rapidity region |η| < 3.2, and for hadronic and forward calorimetry in the region from |η| = 1.5 to |η| = 4.9. After detector consolidation during a long shutdown, Run-2 started in 2015 and about 150 fb$^{-1}$ of data at a center-of-mass energy of 13 TeV was recorded. Phase-I detector upgrades began after the end of Run-2. New trigger readout electronics of the ATLAS Liquid-Argon Calorimeter have been developed. Installation began at the start of the LHC shut down in 2019 and is expected to be completed in 2021. A commissioning campaign is underway in order to realise the capabilities of the new, higher granularity and higher precision level-1 trigger hardware in Run-3 data taking. This contribution will give an overview of the new trigger readout commissioning, as well as the preparations for Run-3 detector operation.

Speaker: Davide Pietro Mungo (Milano)

LAr_PhaseI_Mungo.pdf

70 Run-3 offline data processing and analysis at LHCb

The LHCb detector is undergoing a comprehensive upgrade for data taking in the LHC's Run 3, which is scheduled to begin in 2022. The increased data rate in Run 3 poses significant data-processing and handling challenges for the LHCb experiment. The offline computing and dataflow model is consequently also being upgraded to cope with the factor 30 increase in data volume and associated demands of user-data samples of ever-increasing size. Coordinating these efforts is the charge of the newly created Data Processing and Analysis (DPA) project. The DPA project is responsible for ensuring the LHCb experiment can efficiently exploit the Run 3 data, dealing with the data from the online system with central skimming/slimming (a process known as "Sprucing") and subsequently producing analyst-level ntuples with a centrally managed production system (known as "Analysis Productions") utilising improved analysis tools and infrastructure for continuous integration and validation.It is a multi-disciplinary project involving collaboration between computing experts, trigger experts and physics analysis experts. This talk will present the evolution of the data processing model, followed by a review of the various activities of the DPA project. The associated computing, storage and network requirements are also discussed.

Speaker: Nicola Skidmore

EPS_DPA.pdf

71 Track and Vertex reconstruction in ATLAS for LHC Run 3 and High-Luminosity phases

The determination of charged-particle trajectories (tracking) and the identification of primary collision vertices (vertexing) are complex parts of the event reconstruction chain in collider experiments and constitute the building blocks of most high level analysis objects. During the Run 2 data-taking in ATLAS, tracking was by far the most resource intensive step, for an average number of p-p collisions per bunch crossing (pile-up) ranging from 20 up to 60. The complexity of the combinatorial problem increases dramatically with pile-up and the physics performance degrades as more low-quality tracks with mis-assigned, missing or randomly combined hits are reconstructed.
Averages of around 50 interactions per bunch-crossing are expected during the LHC Run 3, rising to about 200 during the High-Luminosity (HL) phase of the LHC, scheduled to start in about 5 years.
In order to cope with these challenging conditions and to maintain the physics performance reached up to LHC Run 2, a major rewrite of the Run 3 reconstruction software was performed while ATLAS prepares for a replacement of the current ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk) for HL-LHC.
The Run 3 software improvements allowed to dramatically increase the reconstruction speed and pileup robustness. This included replacing the existing ATLAS vertexing with the pioneering use of elements of the ACTS software framework, which will become the backbone of ITk track reconstruction, in production.
In this talk, the improvements achieved for the track and vertex reconstruction to be used in the upcoming LHC Run 3 as well as the latest results on the expected performance of the ITk tracking and of other high-level object identification will be presented.

Speaker: Noemi Calace (CERN)

NoemiCalace_EPS2021_v0.pdf

72 Status and commissioning of the new GE1/1 station for the CMS experiment

The upgrade of the Large Hadron Collider (LHC), with an increase of its luminosity up to 5-7 × 10^34cm^−2s^−1, will cause a huge growth of the background rates expected by the experiments. For this reason, the Compact Muon Solenoid (CMS) experiment is going through an upgrade project, which includes the installation of a new station, called GE1/1, consisting of 144 Triple-Gas Electron Multiplier detectors (GEM). The combined operation of the new GE1/1 station together with the existing Cathode Strip Chamber (CSC) station ME1/1 is expected to improve muon tracking and triggering performance. The installation of the GE1/1 station is complete and the commissioning phase is ongoing. We will present the status of this commissioning and the first results on the performance of the detectors and electronics. Plans for LHC Run 3 will also be discussed.

Speaker: Davide Fiorina (University & INFN Pavia)

DFiorina-EPS-GEMstatus_v2.pdf

73 Status of the Fast Interaction Trigger detector for the ALICE upgrade

During the second Long Shutdown (LS2) of the LHC, ALICE is installing three new detectors and implementing continuous data readout with online reconstruction and data compression. The changes are needed to benefit from the increased luminosity of the LHC during Run 3 and 4. The ALICE interaction rate will increase by two orders of magnitude, reaching 50 kHz for Pb-Pb and up to 1 MHz for pp collisions.

One of the new ALICE detectors is the Fast Interaction Trigger (FIT). Its main functionality includes generating minimum latency interaction triggers (<425 ns), luminosity monitoring with online feedback to the LHC, precision collision time with a resolution better than 40 ps, determination of the centrality and event plane for heavy-ion collisions, and tagging of diffractive and ultra-peripheral events. The FIT detector consists of three subsystems: two fast Cherenkov arrays with 2 cm thick quartz radiators coupled to modified MCP-PMT photosensors (FT0), a large-area scintillator disc (FV0) implementing a novel light collection system, and a Forward Diffractive Detector (FDD). FDD comprises two plastic scintillator arrays with fast wavelength shifting bars, optical fibre bundles, and PMTs. The FDD arrays are located ~20 m at the opposite sides of the interaction point. A brief description of the detector and its functionalities will be given together with the installation and commissioning status.

Speaker: Solangel Rojas Torres (Czech Technical University in Prague (CZ))

Fast-Interaction-Trigger-Update_EPS-2021.pdf

12:00 Lunch Break

Plenary: Welcome and Prize Session

Convener: Thomas Gehrmann (University of Zurich)

74 Welcome from LOC and EPS-HEPP board

Speakers: Johannes Haller (Institut für Experimentalphysik, Universität Hamburg), Sarah Heim (ATLAS (ATLAS Dark Matter with Higgs)), Thomas Gehrmann (University of Zurich), Ties Behnke (FLC (Forschung an Lepton Collidern))

EPS_LOC_Welcome.pdf

recording

75 The High Energy and Particle Physics Prize - award

Speaker: Thomas Gehrmann (University of Zurich)

recording

76 The High Energy and Particle Physics Prize - talk 1

Speaker: Torbjörn Sjöstrand

recording

Sjostrand.pdf

77 The High Energy and Particle Physics Prize - talk 2

Speaker: Bryan Webber

recording

webber_EPS_2021.pdf

78 The Giuseppe and Vanna Cocconi Prize - award

Speaker: Mauro Mezzetto

recording

79 The Giuseppe and Vanna Cocconi Prize - talk

Speaker: Gianpaolo Bellini

EPS-V5_compressed.pdf

recording

80 The Gribov Medal - award

Speaker: Peter Levai

recording

81 The Gribov Medal - talk

Speaker: Bernhard Mistlberger (MIT)

EPS-HEP2021-Mistlberger.pdf

recording

82 The Young Experimental Physicist Prize - award

Speaker: Beate Heinemann (DESY and Freiburg University)

recording

83 The Young Experimental Physicist Prize - talk

Speaker: Nathan Jurik (CERN)

nathan_jurik_yepp.pdf

recording

84 The Young Experimental Physicist Prize - talk

Speaker: Benjamin Nachman (ATLAS (LHC Experiment ATLAS))

EPSYEPPJuly2021.pdf

recording

85 The Outreach Prize - award

Speaker: Anna Lipniacka (University of Bergen (NO) /CERN)

recording

86 The Outreach Prize - talk

Speakers: Ken Cecire, Sascha Mehlhase, Uta Bilow (TU Dresden)

2021-07-26 EPS Outreach Prize BYOPD.pdf

epshep2021jul_imc-v2.pdf

epshep2021jul_imc-v2.pptx

recording

14:05 Break

T01: Astroparticle and Gravitational Waves: Part 2 (GW Theory)

Convener: Diego Blas (KCL)

87 A hybrid simulation of gravitational wave production in first-order phase transitions

The LISA telescope will provide the first opportunity to probe the scenario of a first-order phase transition happening close to the electroweak scale. In thermal transitions, the main contribution to the GW spectrum comes from the sound waves propagating through the plasma. Current estimates of the GW spectrum are based on numerical simulations of a scalar field interacting with the plasma or on analytical approximations -- the so-called sound shell model. In this work we present a novel setup to calculate the GW spectra from sound waves. We use a hybrid method that uses a 1d simulation (with spherical symmetry) to evolve the velocity and enthalpy profiles of a single bubble after collision and embed it in a 3d realization of multiple bubble collisions, assuming linear superposition of the velocity and enthalpy. The main advantage of our method compared to 3d hydrodynamic simulations is that it does not require to resolve the scale of bubble wall thickness. This makes our simulations more economical and the only two relevant physical length scales that enter are the bubble size and the fluid shell thickness (that are in turn enclosed by the box size and the grid spacing). The reduced costs allow for extensive parameter studies and we provide a parametrization of the final GW spectrum as a function of the wall velocity and the fluid kinetic energy.

Speaker: Henrique Rubira (T (Cosmology))

HybridGWsim_EPS.pdf

88 Modeling black hole binaries in scalar-tensor theories of gravity

I will discuss a new formulation of the Einstein equations and scalar tensor theories of gravity--the modified generalized harmonic (MGH) formulation--that allows for the stable, well-posed evolution of black holes in a wide variety of scalar-tensor theories. I will discuss recent progress in numerically modeling binary black hole evolution, and scalar+gravitational wave emission, in the scalar-tensor theory Einstein scalar Gauss-Bonnet gravity.

Speaker: Justin Ripley (DAMPT, University of Cambridge)

mgh.pdf

89 Binary systems as dynamical detectors of gravitational waves

The passage of gravitational waves (GWs) through a binary perturbs the trajectories of the two bodies, potentially causing observable changes to their orbital parameters. In the presence of a stochastic GW background (SGWB) these changes accumulate over time, causing the binary orbit to execute a random walk through parameter space. In this talk I will present a powerful new formalism for calculating the full statistical evolution of a generic binary system in the presence of a SGWB, capturing all six of the binary's orbital parameters. I will show how this formalism can be applied to timing of binary pulsars and lunar laser ranging, thereby setting novel upper limits on the SGWB spectrum in a frequency band that is inaccessible to all other GW experiments.

Speaker: Alex Jenkins (King's College London)

alex-jenkins-binaries-sgwb.pdf

90 Measuring the dark matter environments of black hole binaries with gravitational waves

Black holes of astrophysical and primordial origin can compress their dark matter environments to extreme densities as they form and grow. This "dark dress" inevitably affects the dynamical evolution of binaries, and imprints a characteristic dephasing onto their gravitational waveforms that could be probed with upcoming interferometers. In this work, we study the prospects for detecting and characterizing the dark matter content of these systems with the Laser Interferometer Space Antenna (LISA). We introduce an analytical model for the dephasing of dark dresses motivated by the interplay between the gravitational wave emission and disruption of the dark matter halo that governs their evolution. We demonstrate that LISA could distinguishing dark dresses from standard black hole binaries and quantify how precisely their parameters could be measured. Through such measurements, future gravitational wave detectors could be a powerful tool for probing the particle nature of dark matter.

Speaker: Adam Coogan (GRAPPA, University of Amsterdam)

amcoogan-dark-dress.key

amcoogan-dark-dress.pdf

91 Gravitational Waves as a Big Bang Thermometer

There is a guaranteed background of stochastic gravitational waves produced in the thermal plasma in the early universe. Its energy density per logarithmic frequency interval scales with the maximum temperature Tmax which the primordial plasma attained at the beginning of the standard hot big bang era. It peaks in the microwave range, at around 80 GHz [106.75/gs(Tmax)]^(1/3), where gs(Tmax) is the effective number of entropy degrees of freedom in the primordial plasma at Tmax. We present a state-of-the-art prediction of this Cosmic Gravitational Microwave Background (CGMB) for general models, and carry out calculations for the case of the Standard Model (SM) as well as for several of its extensions. On the side of minimal extensions we consider the Neutrino Minimal SM (νMSM) and the SM-Axion-Seesaw-Higgs portal inflation model (SMASH), which provide a complete and consistent cosmological history including inflation. As an example of a non-minimal extension of the SM we consider the Minimal Supersymmetric Standard Model (MSSM). Furthermore, we discuss the current upper limits and the prospects to detect the CGMB in laboratory experiments and thus measure the maximum temperature and the effective number of degrees of freedom at the beginning of the hot big bang.

Speaker: Carlos Tamarit (Technische Universität München)

Measuring_Tmax.pdf

92 Probing the standard cosmological model with the population of binary black-holes

Gravitational-wave (GW) detections are rapidly increasing in number, enabling precise statistical analyses of the population of compact binaries. In this talk I will show how these population analyses cannot only serve to constrain the astrophysical formation channels, but also to learn about cosmology. The three key observables are the number of events as a function of luminosity distance, the stochastic GW background of unresolved binaries and the location of any feature in the source mass distribution, such as the expected pair instability supernova (PISN) gap. Given data from LIGO-Virgo observations, I will present constraints in cosmological modifications of gravity. I will also discuss future prospects on measuring $H_0$ given a possible population of black holes above the PISN gap. These novel tests of the standard cosmological model require GW data only and will become increasingly relevant as GW catalogs grow, specially if multi-messenger events remain elusive.

Speaker: Jose María Ezquiaga (University of Chicago)

Probing the standard cosmological model with the population of binary black holes

T03: Dark Matter: Part 2

Convener: Elisabetta Baracchini (Gran Sasso Science Institute)

93 Results on Light Dark Matter investigation with CRESST-III

The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) experiment explores with high sensitivity the parameter space of low mass DM candidates, being the pathfinder in the sub-GeV/c^2 mass range. CRESST employs different high-purity crystals and operate them at mK temperature as cryogenic calorimeters The flexibility in employing detectors made of different materials together with the advanced performance of the thermal sensors allow CRESST-III to establish the most stringent limits on spin-dependent and spin-independent low mass DM interactions.

In this contribution, the current stage of the CRESST-III experiment, together with the most recent dark matter results will be presented. The perspective for the next phase of the experiment will be also discussed.

Speaker: Luca Pattavina (INFN - Laboratori Nazionali del Gran Sasso)

cresst_EPS2021_Pattavina.pdf

94 Sub-MeV Dark Matter Searches with EDELWEISS: results and prospects

The Edelweiss collaboration performs light Dark Matter (DM) particles searches with germanium bolometer collecting
charge and phonon signals. Thanks to the Neganov-Trofimov-Luke effect, a RMS resolution of 0.56 electron-hole pair
was obtained on a massive (33.4g) germanium detector operated underground at the Laboratoire Souterrain de Modane.
This sensitiviy made possible a search for Dark Photons Down to 1 eV and for DM-electron interactions below 1 MeV/c2.
It is the first measurement in cryogenic germanium at such low threshold proving the high relevance of this technology.
This is an important step of the development of the Ge detectors with improved performance in the context of the EDELWEISS-SubGeV program.

Speaker: Hugues Lattaud (IP2I)

Sub-MeV_Dark_Matter_Searches_with_EDELWEISS_results_and_prospects.pdf

95 Dark Matter with DAMA/LIBRA

The recent results of DAMA/LIBRA–phase2 experiment deep underground at Gran Sasso are presented. The improved experimental configuration with respect to the phase1 allowed a lower software energy threshold. The DAMA/LIBRA–phase2 data confirm the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature, at high C.L. The model independent DM annual modulation result is compatible with a wide set of DM candidates. In this talk we summarize some of them and perspectives for the future will be outlined.

Speaker: Pierluigi Belli (INFN Roma Tor Vergata)

belli_EPS2021.pdf

96 Annual modulation results from three-year exposure of ANAIS-112

DAMA/LIBRA observation of an annual modulation in the detection rate compatible with that expected for dark matter particles from the galactic halo has accumulated evidence for more than twenty years. It is the only hint about a positive identification of the dark matter, but it is in strong tension with the negative results of other very sensitive experiments. However, this comparison is model-dependent. By using the same target material than DAMA/LIBRA experiment, NaI(Tl), such a comparison is more direct and almost independent in dark matter particle and halo models. In this talk we will present the performance and prospects of ANAIS-112 experiment, which using 112.5 kg of NaI(Tl) as target, is taking data at the Canfranc Underground Laboratory in Spain since August 2017. Results corresponding to three-year exposure will be presented. These results are compatible with the absence of modulation and in tension with DAMA/LIBRA result. Moreover, they support our goal of reaching a 3σ sensitivity to the DAMA/LIBRA result with about 5 years of data.

Speaker: María Luisa Sarsa (CAPA, University of Zaragoza)

EPS_MLSarsa_2021.pdf

97 COSINUS: a NaI-based experiment for Dark Matter search

The COSINUS (Cryogenic Observatory for SIgnals seen in Next-generation Underground Searches) project aims to provide a model-independent cross-check of the long-standing
DAMA/LIBRA claim on the observation of dark matter.

The use of sodium iodide (NaI) crystals, operated at cryogenic temperature as scintillating calorimeters, offers both a low energy threshold for nuclear recoils and the possibility to perform signal-to-background discrimination on an event-by-event basis thanks to the dual and independent read-out of both phonon and light signals.

The construction of the COSINUS apparatus will begin in summer 2021 and the data taking will start in 2022.
In this talk we will present the detection principle and the performance together with status and future prospects of the project.

Speaker: Natalia Di Marco

EPS2021_DMsessionT03_COSINUS_NDiMarco.pdf

98 Directional Dark Matter Search with NEWSdm

In spite of the extensive search for the detection of the dark matter (DM), experiments have so far yielded null results: they are probing lower and lower cross-section values and are touching the so-called neutrino floor. A way to possibly overcome the limitation of the neutrino floor is a directional sensitive approach: one of the most promising techniques for directional detection is nuclear emulsion technology with nanometric resolution. The NEWSdm experiment, located in the Gran Sasso underground laboratory in Italy, is based on novel nuclear emulsion acting both as the Weakly Interactive Massive Particle (WIMP) target and as the nanometric-accuracy tracking device. This would provide a powerful method of confirming the Galactic origin of the dark matter, thanks to the cutting-edge technology developed to readout sub-nanometric trajectories. In this talk we discuss the experiment design, its physics potential, the performance achieved in test beam measurements and the near-future plans. After the submission of a Letter of Intent, a new facility for emulsion handling was constructed in the Gran Sasso underground laboratory which is now under commissioning. A Conceptual Design Report is in preparation and will be submitted in Summer 2021.

Speaker: Giovanni De Lellis

NEWSdm_EPS2021.pdf

T04: Neutrino Physics: Low energy neutrinos

Convener: Justyna Lagoda (NCBJ)

99 Joint measurement of the pure-U235 reactor antineutrino spectrum by STEREO and PROSPECT experiments

STEREO and PROSPECT are very short baseline experiments studying antineutrinos produced by highly-enriched nuclear fuel at the research facilities of Institut Laue-Langevin (Grenoble, France) and Oak Ridge National Laboratory (U.S.A.), respectively. Located at about 10 meters from the reactor cores, they investigate the data-to-prediction deficit called the « Reactor Antineutrino Anomaly » by looking for sterile neutrino oscillations and providing accurate measurements of the U235 antineutrino spectrum.

In this talk I will present a joint analysis performed by the STEREO and PROSPECT collaborations. The two experimental energy spectra have been simultaneously unfolded to provide a reference spectrum in true antineutrino energy for the U235 isotope, achieving the highest precision for pure-U235 experiments. This new experimental reference will be compared to theoretical predictions in order to quantify the observed excess of events around 5 MeV. This measurement proves also to be complementary to the results from experiments using low-enriched nuclear fuel, such as Daya Bay, where several isotopes contribute to the antineutrino spectrum. In addition, I will present the status of the search for sterile neutrinos with the STEREO detector, including preliminary results with the full collected data set.

Speaker: Matthieu Licciardi (LPSC-IN2P3, CNRS, Grenoble, France)

Slides_mLicciardi_EPSHEP21.pdf

100 Latest Neutrino Oscillation Results from the Daya Bay Experiment

This talk will present the latest neutrino oscillation results from the Daya Bay experiment, which consists of eight functionally identical detectors in three experimental sites at different baselines from six 2.9 GW$_{\mathrm{th}}$ nuclear reactor cores. In 1958 days of operation, Daya Bay has collected the largest sample of inverse beta decay events to date, with close to 4 million candidate events. With improved systematics, Daya Bay has produced a world-leading measurement of the $\theta_{13}$ mixing angle and achieved comparable precision for $\Delta m^2_{32}$ to accelerator experiments. Along with the MINOS/MINOS+ and Bugey-3 experiments, Daya Bay has searched for oscillations to light sterile neutrinos, with no significant signal found. The most stringent limits to date have been placed on the $\theta_{\mu e}$ effective mixing angle over five orders of magnitude in the sterile mass-squared difference $\Delta m^2_{41}$, excluding the parameter space allowed by the LSND and MiniBooNE experiments at 90% CL$_\mathrm{S}$ for $\Delta m^2_{41} < 13~\mathrm{eV^2}$.

Speaker: Roberto Mandujano (University of California, Irvine)

EPS2021_DYB_Oscillations.pdf

101 Neutrino oscillation physics in JUNO

Jiangmen Underground Neutrino Observatory, or JUNO, is a future multipurpose neutrino experiment currently being built in China. The data taking with a 20 kt detector, filled with liquid scintillator, will start soon. The main physics goals include estimation of the neutrino mass ordering (NMO) with significance of 3 standard deviations and measurement of neutrino oscillation parameters $\Delta m^2_{32}$, $\Delta m^2_{21}$, $\sin^2\theta_{12}$ with sub-percent precision. Both these measurements will be done based on the observation of electron antineutrino spectrum from multiple nuclear reactors at an average distance of 53 km.

The talk covers the oscillation physics of the JUNO experiment, which is not limited to the reactor neutrino programme, owing to unprecedented energy resolution and large scale of the detector. The measurement of the solar neutrinos from $^8$B will enable JUNO to estimate $\Delta m^2_{21}$ with precision of 20\%, comparable to the current solar experiments. The atmospheric neutrino programme will provide a measurement of the mixing angle $\sin^2\theta_{23}$ and a complementary measurement of NMO. JUNO will be complemented with a satellite detector TAO located at a distance of 30 m from one of the nuclear power plants and will provide a reference measurement of reactor antineutrino spectrum with energy resolution of 2\% at 1 MeV. High energy resolution combined with a short baseline will enable TAO to provide leading constraints on sterile neutrino oscillations in a range of $10^{-2}$ eV$^2\leq\Delta m^2_{41}\leq$8 eV$^2$.

Speaker: Maxim Gonchar (JINR)

epshep21_gonchar_juno_oscillation_v1-1-3.pdf

102 JUNO potential in non-oscillation physics

The Jiangmen Underground Neutrino Observatory (JUNO) is a next-generation liquid scintillator experiment being built in Guangdong province in China. JUNO's target mass of 20 kton will be contained in a 35.4 m acrylic vessel, itself submerged in a water pool, under about 650 m of granite overburden. Surrounding the acrylic vessel are 17612 20'' PMTs and 25600 3'' PMTs. The main goal of JUNO, whose construction is scheduled for completion in 2022, is a 3-4$\sigma$ determination of the neutrino mass ordering (MO) using reactor neutrinos within six years, as well as a precise measurement of $\theta_{12}$, $\delta M_{21}^2$, and $\delta M_{31}^2$.
JUNO's large target mass, low background, and dual calorimetry, leading to an excellent energy resolution and low threshold, allows for a rich physics program with many applications in neutrino physics. The large target mass will allow for high-statistics solar-, geo-, and atmospheric neutrino measurements. JUNO will also be able to measure neutrinos from galactic core-collapse supernovae, detecting about 10,000 events for a supernova at 10 kpc, and achieve a 3$\sigma$ discovery of the diffuse supernova neutrino background in ten years. It can also study non-standard interactions e.g. proton decay, indirect dark matter searches, and probe for lorentz invariance violations. This talk will cover this extensive range of non-oscillation topics on which JUNO will be able to shed light.

Speaker: Alexandre Göttel (Forschungszentrum Jülich - Institute for Nuclear Physics, IKP-2 — RWTH Aachen University - Physics Institute III B)

EPS_HEP.pdf

103 Improved geoneutrinos observation with Borexino detector

Geoneutrinos, which are anti-neutrinos emitted from the decays of long-lived radioactive elements inside the Earth, are unique messengers of internal regions of our planet. The Borexino detector, located at Laboratori Nazionali del Gran Sasso in Italy, is able to detect the geoneutrinos through inverse beta decay reaction. This measurement is feasible thanks to the large scintillator target mass and unprecedented radiopurity, the long distance to nuclear reactors and the natural shielding provided by the Gran Sasso rock.

In this talk, the most updated geoneutrino analysis will be presented, including data from December 2007 to April 2019. Thanks to an improved analysis with optimized data selection cuts, enlarged fiducial volume, and sophisticated cosmogenic veto, the dataset exposure is enhanced by a factor of two with respect to the previous Borexino measurement from 2015.

The statistics increase, along with updated analysis techniques, allowed to measure the geoneutrinos flux with unprecedented precision level, also confirming the presence of a mantle signal. Fundamental geological information about our planet is inferred, as the Uranium and Thorium contents of the mantle, and the Earth radiogenic heat. Moreover, the existence of a possible georeactor located at the center of the Earth has been excluded at 95% C.L.

Speaker: Davide Basilico (University of Milan / INFN Milano)

[EPS-HEP 2021] GeoNeutrinos.pdf

104 Experimental Evidence of neutrinos produced in the CNO fusion cycle in the Sun with Borexino

The proton-proton (pp) chain and the carbon-nitrogen-oxygen (CNO) fusion cycle process are two processes understood theoretically how stars converted hydrogen to helium. Neutrinos emitted in such processes are the only direct probe of the deep interior of the Sun. Borexino is a liquid scintillator detector targeted at measuring solar neutrinos. It is hosted by the underground INFN Laboratori Nazionali del Gran Sasso in L’Aquila, Italy and has achieved unprecedented radio purity of liquid scintillator. Since 2015, the Borexino has made a major effort in stabilizing the thermal condition of the detector aimed at measuring the CNO solar neutrinos, including installation of a passive thermal insulation system and an active temperature control system. It was observed that the movement of the Po-210 backgrounds was significantly suppressed and a low rate region in the center was stably present since 2016. After the Po-210 low-rate-region tracking method was improved, an upper limit of the Bi-210, the critical background of the CNO neutrino signal, was determined. Last fall, Borexino published in Nature the results excluding the absence of the CNO neutrino signal with a significance of five sigmas. The results quantify the relative contribution of CNO fusion in the Sun to be of the order of one percent. It is also the first experimental evidence of the CNO cycle process, the primary mechanism for the stellar conversion of hydrogen in the Universe. Additionally, solar models built from heliuseismoeogy (SSM-HZ) and from spectroscopy (SSM-LZ) predicted inconsistent solar metallicities, known as the “solar metallicity problem”. The CNO neutrino fluxes depend on the carbon and nitrogen abundances. So this work paves the way towards a direct measurement of the solar metallicity using CNO neutrinos. The details of the detector stabilization, the strategy to track the Po-210 low-rate-region, and the strategy to break the correlation between CNO neutrino signals and its backgrounds will be presented.

Speaker: Xuefeng Ding (Gran Sasso Science Institute)

20210726 Experimental Evidence of neutrinos produced in the CNO fusion cycle in the Sun with Borexino.pdf

T05: Heavy Ion Physics: Part 2

Note: All contributions are given 12 minutes + 3 min for questions

105 First LHCb results from PbPb collisions at 5.02 TeV

The LHCb detector is a full spectrometer at forward rapidity covering a pseudorapidity range of 2<eta<5. With its excellent vertex resolution, particle identification and tracking capability, the LHCb is able to perform precision measurements down to very low transverse momentum. We present first LHCb results on heavy flavor in lead-lead collisions at 5.02 TeV, including photoproduction of J/psi mesons in peripheral and ultra-peripheral collisions, and prompt open charm production, using the datasets collected during 2015 and 2018.

Speaker: giulia manca (Università Cagliari & INFN)

Manca_EPS2021_final.pdf

106 Production and ratios of heavy hadrons from large to small collision systems with a coalescence plus fragmentation approach

Measurements of heavy baryon production in $pp$, $pA$ and $AA$ collisions from RHIC to top LHC energies have recently attracted more and more attention, currently representing a challenge for the heavy-quark hadronization theoretical understanding.
The $\Lambda_c/D^0$ ratio observed in $AA$ collision at RHIC and LHC energies has a value of the order of the unity. The recent experimental measurements in $pp$ collisions at $\sqrt{s}=5.02 \,\rm TeV$ have shown a ratio of $\Lambda_c/D^0 \sim 0.6$, about one order of magnitude larger than that measured in $e^+e^-$, $ep$ collisions.
We study the hadronization after the propagation of charm quarks in the quark-gluon plasma (QGP). The propagation is described by means of a relativistic Boltzmann transport approach where the non-perturbative interaction between heavy quarks and light quarks is described by means of a quasi-particle approach.
In this talk we present a coalescence plus fragmentation model for the hadronization and the results obtained in $AA$ collisions for $D^0$, $D_s$, $\Lambda_c$ spectra and the related baryon to meson ratios at RHIC and LHC.
We found a large $\Lambda_c$ production resulting in a baryon over meson ratio of order O(1). This large production has consequences for the D meson nuclear modification factor, that results dumped in the region of low momenta, as observed in STAR data.
Furthermore we present, for the first time, results for these ratios in $pp$ collisions at top LHC energies assuming the formation of an hot QCD matter at finite temperature even for these systems.
We calculate the heavy baryon/meson ratio and the $p_T$ spectra of charmed hadrons with and
without strangeness content: $D^{0}$, $D_{s}$, $\Lambda_{c}^{+}$, $\Sigma_{c}$ and the recently measured $\Xi_c$ baryon, finding an enhancement in comparison with the ratio observed for $e^+e^-$, $ep$ collisions; moreover with this approach we predict also a significant production of $\Omega_c$ respect to $D^0$.

[1] V. Minissale, S. Plumari and V. Greco, arXiv:2012.12001 [hep-ph].
[2] S. Plumari, V. Minissale, S.K. Das, G. Coci and V. Greco, Eur.Phys.J. C 78 (2018) no.4, 348
[3] F. Scardina, S. K. Das, V. Minissale, S. Plumari, V. Greco, Phys.Rev. C 96 (2017) no.4, 044905

Speaker: Vincenzo Minissale (Università degli Studi di Catania - INFN LNS)

Minissale_EPS-HEP2021.pdf

107 Quarkonia measurements in nucleus-nucleus collisions with ALICE

The production of quarkonia is one of the first proposed probes of the QGP properties in heavy-ion collisions. Since heavy quarks are produced during the early hard partonic collisions, they experience the entire evolution of the fireball. The suppression of quarkonium bound states by the free color charges of the dense deconfined medium, as well as the charmonium regeneration by (re)combination of charm quarks at the QGP phase boundary or through the fireball evolution, are sensitive to the medium properties. Furthermore, a modification of the quarkonium vector states polarization in Pb—Pb collisions with respect to pp collisions may give further insights on quarkonium suppression and regeneration mechanisms in the QGP. In addition, to the study of quarkonia in inelastic heavy-ion collisions, coherent photonuclear production of vector mesons can be studied by the virtue of the strong electromagnetic fields generated by ultrarelativistic heavy ions to infer information on the wave function of the nuclei that are crucial for the understanding of the initial state of heavy-ion collisions.

In this contribution, we will report on the recent ALICE measurements of the nuclear modification factor $R_{\rm AA}$ of J/$\psi$ as a function of centrality/$p_{\rm T}$, and on final J/$\psi$ $v_2$ results, at both mid- and forward rapidity, using the full Run 2 Pb—Pb data sample ($\sqrt{s_{\rm NN}}$=5.02 TeV). The final results on 𝚼(1S) $R_{\rm AA}$ and $v_2$, 𝚼(2S) $R_{\rm AA}$, and J/$\psi$ $v_3$ measured at forward rapidity will also be shown. We will also report on the first measurement of the J/$\psi$ polarization in Pb—Pb collisions as a function of $p_{\rm T}$ and of the collision centrality, providing prospects for measurements as a function of the event plane. The aforementioned results will be compared and confronted to theoretical model predictions. Furthermore, we will discuss recent ALICE results on photonuclear production of $\rho$ and J/$\psi$ mesons in ultra-peripheral collisions.

Speaker: Kunal Garg (SUBATECH)

EPS2021_Kunal_v5.pdf

108 Jet substructure measurements in heavy-ion collisions with ALICE

Jet substructure measurements, based on the distribution of constituents within a jet, are able to probe specific regions of QCD radiation phase space for jet showers in vacuum. This powerful capability provides new opportunities to study the dynamics of jet quenching in heavy-ion collisions and to help reveal the micro-structure of the quark-gluon plasma. The ALICE experiment is particularly well-suited for jet substructure measurements in heavy-ion collisions, due to its high-precision tracking system and focus on low transverse momentum jets. In this talk, we report several new jet substructure measurements in Pb-Pb collisions at $\sqrt{s_\rm{NN}}=5.02$ TeV by the ALICE Collaboration. These include the first fully corrected measurements of the groomed jet momentum fraction, $z_{g}$, and the groomed jet radius, $\theta_{g} \equiv R_{g}/R$, as well as the $N$-subjettiness distribution and the fragmentation distribution of reclustered subjets. The measurements will be compared to theoretical calculations and provide new constraints on the physics underlying jet quenching.

Speaker: James Mulligan

20210726_Mulligan_EPS-HEP.pdf

109 Multi-partonic medium induced cascades in expanding media

Going beyond the simplified gluonic cascades, we have introduced both gluon and quark degrees of freedom for partonic cascades inside the medium. We then solve the set of coupled evolution equations numerically with splitting kernels calculated for exponential and Bjorken expanding media to arrive at medium-modified parton spectra for quark and gluon initiated jets respectively. Firstly, we have studied the inclusive jet $R_{AA}$ by including phenomenologically driven combinations of quark and gluon fractions inside a jet. The impact of the rapidity dependence of the jet $R_{AA}$ has been studied in detail. Secondly, we have studied the path-length dependence of jet quenching for different types of expanding media by calculating the jet $v_2$. Additionally, we have qualitatively studied the sensitivity of the time for the onset of the quenching for the Bjorken profile on jet $v_2$ and comparison with data from ATLAS.

Speaker: Souvik Priyam Adhya (Institute of Particle and Nuclear Physics, Faculty of Mathematics and Physics, Charles University)

eps_hep21_souvik.pdf

110 Quenching effects in the jet spectrum at various cone sizes

The strong suppression of high-pT jets in heavy-ion collisions is a result of elastic and inelastic energy loss, suffered by the jet multi-prong collection of color charges that are resolved by medium interactions. We develop a novel analytic framework to study the quenched jet spectrum in which we include many energy-loss-related effects, such as resummation of soft and hard medium induced emissions, broadening, elastic scattering, jet fragmentation, cone size, coherence effects, etc. We present the first predictions for the nuclear modification factor and the quantile procedure with cone size dependence. We compare dijet and boson+jet events to unfold the spectrum bias effects and improve quark-, and gluon-jet classification in heavy-ion jets. Besides pointing out its flexibility, we show our formalism relevance in pp jets modeling non-perturbative effects.

The talk is based on arXiv:2101.01742 and arXiv:2103.14676

Speaker: Adam Takacs (University of Bergen)

Adam_Takacs_EPS-HEP_2021.pdf

111 Exploring jet fragmentation using two-particle correlations with $\Lambda$ and K$^0_{\rm S}$ as trigger particles in pp and Pb–Pb collisions with ALICE

Complementary to jet reconstruction, two-particle correlations in $\Delta\eta$ and $\Delta\varphi$ are used to study jets, in particular their particle composition. While in Pb–Pb collisions this is done to characterize the quark–gluon plasma, pp and p–Pb collisions serve as a reference and are of interest on their own for their input into the understanding of particle production mechanisms. Recent ALICE results on the production of strange particles in small systems (pp and p–Pb collisions) reveal the possibility of having similar strange hadron production mechanisms in all collision systems. We present here a study of two-particle correlations triggered with strange hadrons (K$^0_{\rm S}$, $\Lambda$, $\bar{\Lambda}$) in pp collisions at 13 TeV and 5.02 TeV and in the most central Pb–Pb collisions at $\sqrt{s_{\rm NN}}=$ 5.02 TeV. The dependence of the per-trigger yields of primary charged hadrons on the transverse momenta of the trigger and associated particles, as well as on the event multiplicity, will be presented for both the near-side and away-side regions. Moreover, the ratios of these yields to the yields extracted from inclusive hadron-hadron correlations and the nuclear modification factor $I_{\rm AA}$ will be discussed. The results are compared among the three hadron species. In addition, a comparison to different Monte Carlo generators is presented, which allows us to better understand the strangeness production in jets.

Speaker: Lucia Husova

jetFragmentation_EPS.pdf

112 Deep learning jet modifications in heavy-ion collisions

Jet interactions in a hot QCD medium created in heavy-ion collisions are conventionally assessed by measuring the modification of the distributions of jet observables with respect to the proton-proton baseline. However, the steeply falling production spectrum introduces a strong bias toward small energy losses that obfuscates a direct interpretation of the impact of medium effects in the measured jet ensemble. In this talk, we will explore the power of deep learning techniques to tackle this issue on a jet-by-jet basis.

Toward this goal, we employ a convolutional neural network (CNN) to diagnose such modifications from jet images where the training and validation is performed using the hybrid strong/weak coupling model. By analyzing measured jets in heavy-ion collisions, we extract the original jet transverse momentum, i.e., the transverse momentum of an identical jet that did not pass through a medium, in terms of an energy loss ratio. Despite many sources of fluctuations, we achieve good performance and put emphasis on the interpretability of our results. We observe that the angular distribution of soft particles in the jet cone and their relative contribution to the total jet energy contain significant discriminating power, which can be exploited to tailor observables that provide a good estimate of the energy loss ratio.

With a well-predicted energy loss ratio, we study a set of jet observables to estimate their sensitivity to bias effects and reveal their medium modifications when compared to a more equivalent jet population, i.e., a set of jets with similar initial energy. Then, we show how this new technique provides unique access to the initial configuration of jets over the transverse plane of the nuclear collision, both with respect to their production point and initial orientation. Finally, we demonstrate the capability of our new method to locate with unprecedented precision the production point of a dijet pair in the nuclear overlap region, in what constitutes an important step forward towards the long term quest of using jets as tomographic probes of the quark-gluon plasma.

[1] Yi-Lun Du, Daniel Pablos, Konrad Tywoniuk, Deep learning jet modifications in heavy-ion collisions, arXiv:2012.07797 [hep-ph], JHEP. 2021, 206 (2021)

Speaker: YILUN DU (University of Bergen)

EPS_HEP21_Yilun.pdf

T06: QCD and Hadronic Physics: Part 2: Jets

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Mateusz Dyndal (AGH UST Krakow)

113 Precision measurements of jet production at the ATLAS experiment

Measurements of jet production are sensitive to the strong coupling constant, high order perturbative calculations and parton distribution functions. In this talk we present the most recent ATLAS measurements in this area at a centre-of-mass energy of sqrt(s) = 13 TeV. We present measurements of variables probing the properties of the multijet energy flow and of the Lund Plane using charged particles. We will also present new measurements sensitive to the strong coupling constant. All of the measurements are corrected for detector effects and are compared to the predictions of state-of-the-art Monte Carlo event generators.

Speaker: mario campanelli (UCL)

EPSJets2021.pdf

114 Recent jet measurements in CMS

Measurement of inclusive jet cross sections in proton collisions at 5 and 13 TeV with the CMS experiment are presented. Measurements are performed as a function of the jet transverse momentum pT and jet rapidity. Jets are reconstructed using the anti-kT clustering algorithm with different size parameters in a wide phase space region in jet pT and jet rapidity. The measured jet cross sections are corrected for detector effects and compared with the predictions from perturbative QCD.

Speaker: Patrick Connor (Uni Hamburg (Institut fur Experimentalphysik & CDCS))

talk.pdf

115 Groomed jet mass in lepton collisions at high precision

We present predictions of the distribution of groomed heavy jet mass in electron-positron collisions at the next-to-next-to-leading order accuracy matched with the resummation of large logarithms to next-to-next-to-next-to-leading logarithmic accuracy. Resummation at this accuracy is possible through extraction of necessary two-loop constants and three-loop anomalous dimensions from fixed-order codes. The talk will be based on published papers on arXiv: 2002.00942 and 2002.05730.

Speaker: Zoltan Trocsanyi (ELTE Eotvos Lorand University)

Trocsanyi-groomedJM.pdf

116 Measurement of the primary Lund jet plane density in pp collisions at $\sqrt{s} = \rm{13}$ TeV with ALICE

Precision measurements of jet substructure are used as a probe of fundamental QCD processes. The primary Lund jet plane density is a two-dimensional visual representation of the radiation off the primary emitter within the jet that can be used to isolate different regions of the QCD phase space.
A new measurement of the primary Lund plane density for inclusive charged-particle jets in the transverse momentum range of $20 \leq p_{\rm{T,jet}}^{\rm ch} \leq 120$ GeV$/c$ in pp collisions at $\sqrt{s} =$ 13 TeV with the ALICE detector will be presented. This is the first measurement of the Lund plane density in an intermediate jet $p_{\rm T}$ range where hadronization and underlying event effects play a dominant role. The projections of the Lund plane density onto the splitting scale $k_{\rm{T}}$ and splitting angle $\theta$ axis are shown, highlighting the perturbative/non-perturbative and wide/narrow angle regions of the splitting phase space. Through a 3D unfolding procedure, the Lund plane density is corrected for detector effects which allows for quantitative comparisons to MC generators to provide insight into how well generators describe different features of the parton shower and hadronization.

Speaker: Laura Havener

ALICELundPlane_EPSHEP2021_Havener_v3.pdf

117 Jet substructure measurements in CMS

Various measurements related to the study of hadronic jets substructure in proton collisions at 13 TeV with the CMS experiment are presented. The differential jet production cross section as a function of the jet mass and transverse momentum is shown in events with a Z boson plus jet topology, with and without the soft radiation within a jet removed by a jet grooming algorithm. Measurement of jet substructure observables describing the distribution of particles within quark- and gluon-initiated jets, are carried out with both dijet and Z plus jet event samples. The cross section of hadronically decaying W/Z bosons identified using jets with a large cone radius at large transverse momenta together with jet substructure identification criteria, are also presented.

Speaker: Suman Chatterjee (Austrian Academy of Sciences (AT))

EPS2021_Suman.pdf

118 Jet substructure measurements in proton-proton collisions with ALICE

Jets can be used to test our understanding of quantum chromodynamics (QCD). Specifically, jet-substructure observables measured in proton-proton (pp) collisions constrain perturbative (p)QCD calculations, as well as non-perturbative physics effects such as hadronization, and serve as a baseline to compare to measurements in heavy-ion collisions, where a deconfined state of matter is expected to be formed. The significant scale difference between the parton
from the hard-scattering process and the hadrons measured in the detector creates a large phase space for the jet formation and evolution. Consequently, no single measurement can fully constrain the jet behavior, and a suite of observables needs to be studied simultaneously. In this talk we present an overview of recent charged-jet substructure and jet shape measurements from pp collisions in ALICE, including generalized angularities of groomed and inclusive jets, angular distances between different jet axes, and the radial distributions of heavy-flavour jets identified by the presence of a D$^0$ meson or $\Lambda_{c}$ baryon among its constituents. An iterative declustering technique is also used to trace all branching of the charm quark revealing the dead-cone effect for the first time in hadronic collisions. These new results provide new insights into the evolution of jets by comparing our measurements to predictions from different event generators and pQCD calculations.

Speaker: Vit Kucera (CERN)

jet_substructure.pdf

119 Measurement of 1-jettiness in deep-inelastic scattering at HERA

A first measurement of the 1-jettiness event shape observable in neutral-current deep-inelastic electron-proton scattering is presented. The 1-jettiness observable $\tau^1_b$ is defined such that it is equivalent to the thrust observable in the Breit frame, following momentum conservation. The data were taken with the H1 detector at the HERA $ep$ collider at a center-of-mass energy of 319 GeV in the years 2003 to 2007 and correspond to an integrated luminosity of about 351pb$^{-1}$. The triple-differential cross sections are presented as a function of the 1-jettiness $\tau^1_b$, the event virtuality $Q^2$ and the Bjorken-variable $x_\text{Bj}$ in the kinematic region $Q^2>150$\,GeV$^2$. The data have high sensitivity to the parton distribution functions of the proton, the strong coupling constant and to resummation and hadronisation effects. The data are compared to selected predictions.

Speaker: Johannes Hessler (ATLAS (LHC Experiment ATLAS))

OneJettinessH1.pdf

120 QCD jet production at a high energy muon collider

After the triumph of discovering the Higgs boson at the CERN Large Hadron Collider, people are getting increasingly interested in studying the Higgs properties in detail and searching for the physics beyond the Standard Model (SM). A multi-TeV lepton collider provides a clean experimental environment for both the Higgs precision measurements and the discovery of new particles. In high-energy leptonic collisions, the collinear splittings of the leptons and electroweak (EW) gauge bosons are the dominant phenomena, which could be well described by the parton picture. In the parton picture, all the SM particles should be treated as partons that radiated off the beam particles, and the electroweak parton distribution functions (EW PDFs) should be adopted as a proper description for partonic collisions of the initial states. In our work, both the EW and the QCD sectors are included in the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) formalism to perturbatively resum the potential large logarithms emerging from the initial-state radiation (ISR). I will show the results of QCD jet production as well as some other typical SM processes at a possible high-energy electron-positron collider and a possible high-energy muon collider obtained using the PDFs.

Speaker: Yang Ma (University of Pittsburgh)

EPS2021.pdf

T07: Top and Electroweak Physics: Part 2

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Alexander Grohsjean (CMS (CMS Fachgruppe TOP)), Eleni Vryonidou

121 Measurements of top quark pair production cross sections with the ATLAS detector at the LHC

Comprehensive measurements of inclusive and differential cross-sections for top-quark production are presented. The cross section for production of top-quark-antiquark pair is measured in the dilepon, lepton+jets and all-hadronic channels as function of kinematic properties the top quarks and of their final decay products, also including final states featuring top quarks with high transverse momenta compared to the top quark mass.
Measurements use data from LHC proton-proton collisions recorded during the entire Run2 at both 13 and 5 TeV center-of-mass energy.
The differential measurements are compared quantitatively to several setups of next-to-leading order matrix-element generators combined with parton-shower generators.

Speaker: Federica Fabbri

FFabbri_EPS2020.pdf

122 Inclusive and differential ttbar cross-section measurements at CMS

Latest CMS measurements of top quark pair production, inclusive and/or differential is presented. Boosted regime is included in this talk.

Speaker: Javier Fernandez (Universidad de Oviedo - ICTEA)

fernandez.pdf

123 Top pair production at NNLO matched to parton showers

We present the first matched computation of top-quark pair production at next-to-next-to-leading order (NNLO) in QCD with all-order radiative corrections as implemented via parton-shower (PS) simulations. This result has been obtained by constructing the MiNNLOPS method for the production of heavy quarks, which constitutes the first NNLO+PS prediction for reactions with colour charges in the final state in hadronic collisions. Our results are of crucial importance for LHC phenomenology, while also representing an important step towards the NNLO+PS simulation of other hadronic processes with colour charges in the final state.

Speaker: Javier Mazzitelli

mazzitelli_ttbar_MiNNLO.pdf

124 Top-quark production at approximate N3LO

I discuss recent theoretical results with soft-gluon corrections for various top-quark production processes through approximate N3LO, including soft anomalous dimensions through three loops. I present numerical results for total cross sections as well as single- and double-differential distributions for top-pair and various single-top processes, including three-particle final states, and I show that soft-gluon corrections are dominant for a large range of collider energies.

Speaker: Nikolaos Kidonakis (Kennesaw State University)

Kidonakis.pdf

125 Testing the Standard Model in boosted top quark production with the ATLAS experiment at the LHC

Measurements in boosted top quark production test the Standard Model in a previously unexplored regime with a strongly enhanced sensitivity to high-scale new phenomena. Dedicated techniques have been developed to reconstruct and identify boosted top quarks. In this contribution measurements of the ATLAS experiment are presented of the differential cross section and asymmetries in this extreme kinematic regime. The measurements are interpreted within the Standard Model Effective Field Theory, yielding stringent bounds on the Wilson coefficients of two-light-quark-two-quark operators.

Speaker: Peter Berta (Charles University, Prague)

EPS_talk_final_PeterBerta_26.7.2021.pdf

126 Measurements of single top quark production cross sections with the ATLAS detector at the LHC

The inclusive cross section for production of a single top quark production in association with a W boson is measured in both the dilepton and in the lepton+jets final state. Events are are selected requiring two (one) charged leptons and one or two (at least three) jets with at most two (one) jets (jet) identified as containing b hadrons. Multivariate discriminants are constructed to separate the tW signal from the dominant top-quark pair̄ background. Measurements use data from LHC proton-proton collisions recorded during Run2 at both 13 and 8 TeV center-of-mass energy

Speaker: Rui Zhang

EPS2021ZhangRui.pdf

127 CMS results of top quark electroweak production, including associated productions

Latest CMS measurements of single top quark, inclusive and/or differential is presented. The talk also covers single top production in association with additional bosons.

Speaker: Luka Lambrecht (Ghent University (BE))

eps_2021_singletop.pdf

128 Soft Gluon Resummation for the Associated Single Top and Higgs Production at the LHC

Processes involving the Higgs boson and the top quark are of high interest in searches for BSM physics because they allow to directly measure the top Yukawa coupling. Although it has a relatively small cross section, the single top and Higgs production process pp → Htj is particularly sensitive to new physics, calling for precise theoretical predictions. For many processes at the LHC, a reduction of theoretical uncertainties can be achieved by means of resummation techniques, accounting for large logarithmic corrections, which originate from soft gluon emissions. In this talk, we discuss extending the precision with which theoretical predictions for the s-channel tHj production are known from NLO (next-to-leading order) to NLO+NLL (next-to-leading logarithmic matched to NLO) accuracy.

Speaker: Laura Moreno Valero (Westfälische Wilhelms Universität Münster)

EPS2021_LauraMorenoValero.pdf

T08: Flavour Physics and CP Violation: Part 2

Conveners: Francesco Dettori (Università degli Studi di Cagliari), Trabelsi Karim (BELLE (BELLE II Experiment))

129 CP violation in charmless 2-body B meson decays at LHCb

Measurements of CP asymmetries in charmless two-body B-meson decays can be a powerful way to provide stringent tests of the Standard Model. In particular a longstanding anomaly in the CP asymmetries of B decays to a kaon and a pion, known as the K$\pi$ puzzle, can be a hint of physics beyond the Standard Model. We present new results from the analyses of charmless 2-body B decays with kaons and pions in the final state at LHCb.

Speaker: Thomas Grammatico (LPNHE)

EPS-HEP_grammatico.pdf

130 NNLO QCD corrections to B-meson mixing

The flavor mixing parameter $\Delta \Gamma_{12}^s$ that governs the lifetime differences of neutral $B_s$ mesons suffers from large uncertainties related to the uncalculated perturbative corrections. In this talk I will present new results on the previously unknown NNLO QCD corrections to the $B_s - \bar{B}_s$ mixing process that lead to a reduction of theoretical errors on $\Delta \Gamma_{12}^s$. To this end, we perform a fully analytic evaluation of the current-current correlators at 3 loops, as well as the current-penguin and current-chromomagnetic correlators at 2 loops in the $\Delta B = 1$ effective Hamiltonian. Some interesting aspects of this calculation to be addressed in my talk involve higher-order matching between two effective field theories ($\mathcal{H}_{\textrm{eff}}^{\Delta B = 1}$ and $\mathcal{H}_{\textrm{eff}}^{\Delta B = 2}$), dedicated treatment of evanescent operators in the presence of dimensionally regulated IR divergences, asymptotic expansion of the amplitudes in $m_c/m_b$ up to $\mathcal{O}(m_c^2)$ and the analytic evaluation of the resulting 3-loop on-shell integrals with one mass scale.

Speaker: Vladyslav Shtabovenko (KIT)

talk_shtabovenko.pdf

131 Beauty to open charm final states at LHCb

The latest studies of beauty meson decays to open charm final states from LHCb are presented. Several first observations and branching fraction measurements using Run 1 and Run 2 data samples are shown. These decay modes will provide important inputs to other analyses, and may be used for future measurements of CP violation.

Speaker: Fionn Bishop (Cavendish Laboratory, University of Cambridge)

BeautyToOpenCharmLHCb_FBishop_EPS21.pdf

132 Probing squared four-fermion operators of SMEFT with meson-mixing

The Standard Model Effective Field Theory (SMEFT) is a universal way of probing New Physics (NP) manifesting as new, heavy particle interactions with the Standard Model degrees of freedom, that respect the SM gauged symmetries. Higher order terms in the NP interactions possibly lead to large effects, mandatory for meaningful phenomenological studies, such as contributions to neutral meson-mixing, which typically pushes the scale of NP to energy scales much beyond the reach of direct searches in colliders. I discuss for the first time the leading-order renormalization of double-insertions of dimension-6 four-fermion operators that change quark flavor by one unit (i.e., $ | \Delta F | = 1 $, $ F = $ strange-, charm-, or bottom-flavor) by dimension-8 operators relevant for meson-mixing (i.e., $ | \Delta F | = 2 $) in SMEFT, and consider the phenomenological implications of contributions proportional to relatively large Yukawas. Given the underlying interest of SMEFT to encode full-fledged models at low-energies, this work stresses the need of considering dimension-8 operators in phenomenological applications of dimension-6 operators of SMEFT.

Speaker: Luiz Vale Silva

Vale_Silva_1.pdf

133 Measurements of $B\to D^{(*)}K$ and $B\to D^{(*)}\pi$ related to the determination of $\gamma$ at Belle II

he CKM angle $\gamma$ ($\phi_3$) of the unitarity triangle is the only one that is accessible with tree-level decays in a theoretically clean way. The key method to measure $\gamma$ is through the interference between $B^+\to D^0 K^+$ and $B^+ \to \bar D^0 K^+$ decays that occurs if the final state of the charm-meson decay is accessible to both the $D^0$ and $\bar D^0$ mesons. The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. Belle II experiment aims to record 50 ab$^{-1}$ of data, a factor of 50 more than its predecessor. With the ultimate Belle II data sample of 50 ab$^-1$, a determination of $\gamma$ with a precision of 1 degree or better is foreseen. Main operation of SuperKEKB started in March 2019 and results from the full available Belle II data set, which corresponds to approximately 100~fb$^{-1}$, will be presented. The ratios of decay rates of $\Gamma(B^-\to D^{(*)0}K^-)/\Gamma(B^-\to D^{(*)0}\pi^-)$ and $\Gamma(\bar{B}^0\to D^{(*)+}K^-)/\Gamma(\bar{B}^0\to D^{(*)+}\pi^-)$ are measured. In addition, more detailed studies of $B^{-}\to D(K_{\rm S}^0\pi^{+}\pi^{-})K^-$, $B^{-}\to D(K_{\rm S}^0\pi^{0})K^-$ and $B^{-}\to D^{*0}(D^0\pi^0)K^-$ decays are described; these modes are key to the accurate determination of $\gamma$ at Belle II.

Speaker: Benedikt Wach (BELLE (BELLE II Experiment))

EPS2021_BenediktWach.pdf

134 ATLAS measurements of CP violation with beauty mesons

The ATLAS experiment has performed measurements of mixing and CP violation in the neutral B meson systems.
This talk will focus on the latest results from the ATLAS collaboration on CP violation in the B_s^0 —> J/psi phi decays.
Standard Model predicts the CP violating mixing phase, phi_s, to be very small and its SM value is very well constrained,
while in many new physics models large phi_s values are expected. Latest measurements of phi_s and several other parameters
describing the B_s^0 —> J/psi phi decays will be reported.

Speaker: Radek Novotny (UNM)

EPS-HEP2021_Novotny.pdf

135 Charmless three-body decays at LHCb

Short and long-distance dynamics along with a sizeable effective weak phase caused by the interference between tree and penguin amplitudes in charmless 3-body B decays leads to a rich structure of CP violation as a function of the phase space. We present the latest studies with charmless $B \to 3h$ decays at LHCb, including CP asymmetries and branching fractions

Speaker: Lais Soares Lavra (Laboratoire de Physique de Clermont)

EPS-2021-Lais-Soares-Lavra.pdf

136 Light hyperon physics at BESIII

The BESIII experiment at the electron positron collider BEPCII in Beijing is successfully operating since 2008 and has collected large data samples in the tau-mass region, including the world’s largest data samples at the J/ψandψ(2S) resonances. The recent observations of hyperon polarizations at BESIII, which opens a new window for searching new physics beyond the SM, also attracts both experimental and theoretical attentions. In this presentation recent results on hyperon physics achieved at BESIII will be highlighted.

Speaker: Viktor Thorén (Uppsala University)

EPSHEP_Hyperons_Thoren.pdf

T09: Higgs Physics: Precision - part 2 / Yukawa - part 1

Conveners: Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris), meng xiao (zhejiang university), Michael Trott (NBI), Sarah Heim (DESY)

137 Higgs-plus-jet differential distributions as stabilizers of the high-energy resummation

We investigate the inclusive hadroproduction of a Higgs boson in association with a jet, featuring large transverse momenta and separated by a large rapidity distance. We propose this reaction, that can be studied at the LHC as well as at new-generation colliding machines, as a novel probe channel for the manifestation of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. We bring evidence that high-energy resummed distributions in rapidity and transverse momentum exhibit a solid stability under higher-order corrections, thus offering us a faultless chance to gauge the feasibility of precision calculations of these observables at high energies. We come out with the message that future, exhaustive analyses of the inclusive Higgs-boson production, would benefit from the inclusion of high-energy effects in a multi-lateral formalism where distinct resummations are concurrently embodied. We propose these studies with the aim of inspiring synergies with other Communities, and pursuing the goal of widening common horizons in the exploration of the Higgs-physics sector.

Speaker: Francesco Giovanni Celiberto (ECT*/FBK Trento & INFN-TIFPA)

talk_EPS-HEP_2021_Celiberto_Higgs-jet.pdf

138 Precise predictions of the mass of the discovered Higgs boson in supersymmetric scenarios

The mass of the discovered Higgs boson is one of its most precisely measured properties with an experimental accuracy at the sub-percent level. Besides its coupling behaviour, which conforms so far with the prediction of the Standard Model, the measured Higgs mass value can place strong constraints on extensions of the Standard Model, in particular supersymmetric ones. To fully exploit this experimental accuracy, a very precise prediction of the mass of the Standard Model-like Higgs boson in the respective model is required.

In this talk, I will comment on different methods to calculate the mass and present some recent developments in the effort of improving the predictions within supersymmetric extensions of the Standard Model. In particular, I will consider scenarios with heavy supersymmetric partner particles but relatively light Higgs bosons with and without CP-violation.

Speaker: Heidi Rzehak (University of Tübingen)

EPS2021.pdf

139 Measurements and interpretations of Higgs boson production using decays to two b-quarks with the ATLAS detector

Testing the couplings of the Higgs boson to quarks is important to understand the origin of quark masses. The talk presents Simplified Template Cross Section measurements for Higgs boson production in association with a vector boson using decays to two b quarks using pp collision data collected at 13 TeV, along with an interpretation in an Effective Field Theory framework. A search for vector-boson fusion production in the same Higgs decay channel will also be presented.

Speaker: Karol Krizka (Lawrence Berkeley National Laboratory)

eps-20210726.pdf

140 Higgs boson coupling to second generation fermions with the ATLAS detector

Searches for Higgs boson decays to two second-generation quarks or leptons, based on 13 TeV pp collision data, are presented, as well as indirect constraint of the Yukawa coupling of the Higgs boson to the charm quark.

Speaker: Marko Stamenkovic (Nikhef)

202010726_EPS_MarkoStamenkovic.pdf

141 Measurements of Higgs production and decay in final states involving quarks (CMS)

The latests CMS results collected at a centre-of-mass energy of 13 TeV and focusing on Higgs boson production and decay in final states involving quarks (ttH, tH, VH Hbb, VH Hcc) will be discussed.

Speaker: Aliya Nigamova (University of Hamburg)

EPS2021_HbbHcc.pdf

142 The h(125) decays to c cbar, b bbar, b sbar, photon photon and gluon gluon in the light of the MSSM with quark flavor violation

We study the Higgs boson decays h -> c cbar, b bbar, b sbar, photon photon
and gluon gluon in the Minimal Supersymmetric Standard Model (MSSM) with
general quark flavor violation (QFV), identifying the h with the Higgs boson
with a mass of 125 GeV. We compute the widths of the h decays to c cbar,
b bbar, b sbar (s bbar) at full one-loop level in the MSSM with QFV.
For the h decays to photon photon and gluon gluon we compute the widths
at NLO QCD level. We perform a MSSM parameter scan respecting theoretical
constraints from vacuum stability conditions and experimental constraints,
such as those from K- and B-meson data and electroweak precision data, as
well as recent limits on Supersymmetric (SUSY) particle masses and the
125 GeV Higgs boson data from LHC experiments.

From the parameter scan, we find the followings:

(1) DEV(h -> c cbar) and DEV(h -> b bbar) can be very large simultaneously:
DEV(h -> c cbar) can be as large as ~ +/-60% and
DEV(h -> b bbar) can be as large as ~ +/-20%.
Here DEV(h -> X Y) is the deviation of the decay width Gamma(h -> X Y)
in the MSSM from the SM prediction:
DEV(h -> X Y) = Gamma(h -> X Y)_MSSM / Gamma(h -> X Y)_SM - 1.

(2) The QFV decay branching ratio BR(h -> b sbar / bbar s) can be as
large as about 0.17% in the MSSM. It is almost zero in the SM.
The sensitivity of ILC(250 + 500 + 1000) to this decay BR could be
about 0.1% at 4 sigma signal significance.

(3) DEV(h -> photon photon) and DEV(h -> gluon gluon) can be large
simultaneously: DEV(h -> photon photon) can be as large as about + 4% and
DEV(h -> gluon gluon) can be as large as about -15%.

(4) There is a very strong correlation between DEV(h -> photon photon)
and DEV(h -> gluon gluon). This correlation is due to the fact that the
stop-loop (stop-scharm mixture loop) contributions dominate the two DEVs.

(5) The deviation of the width ratio Gamma(h -> photon photon)/Gamma(h ->
gluon gluon) in the MSSM from the SM value can be as large as about +20%.

(6) All of these large deviations in the h decays are due to large
scharm-stop mixing and large stop/scharm involved trilinear couplings
T_{U23}, T_{U32}, T_{U33} and large sstrange-sbottom mixing and large
sstrange/sbottom involved trilinear couplings T_{D23}, T_{D32}, T_{D33}.

(7) ILC can observe such large deviations from SM at high signal significance.

(8) In case the deviation pattern shown here is really observed at ILC,
then it would strongly suggest the discovery of QFV SUSY (MSSM with QFV).

Note: This work is based on collaboration with H. Eberl and E. Ginina (HEPHY Vienna).

References:
Phys. Rev. D 91 (2015) 015007 [arXiv:1411.2840 [hep-ph]]
JHEP 1606 (2016) 143 [arXiv:1604.02366 [hep-ph]]
IJMP A34 (2019) 1950120 [arXiv:1812.08010 [hep-ph]]

Speaker: Keisho Hidaka (Tokyo Gakugei University)

Hidaka@EPS-HEP2021.pdf

Hidaka@EPS-HEP2021.pptx

143 Resurrecting bbh with Machine Learning Magic

The associated production of a $b\bar{b}$ pair with a Higgs boson could provide an important probe to both the size and the phase of the bottom-quark Yukawa coupling, $y_b$. However, the signal is shrouded by several irreducible background processes. We show that the analysis of kinematic shapes provides us with a concrete prescription for separating the $y_b$-sensitive production modes from both the irreducible and the QCD-QED backgrounds in the $b\bar{b}\gamma\gamma$ final state. We draw a page from game theory and use Shapley values to make Boosted Decision Trees interpretable in terms of kinematic measurables and provide physics insights into the variances in the kinematic shapes of the different channels that help us complete this feat. Adding interpretability to the machine learning algorithm opens up the black-box and allows us to pick and interpret upon kinematic variables that matter most in the analysis. We resurrect the hope of constraining the size and, possibly, the phase of $y_b$ using kinematic shape studies of $b\bar{b}h$ production with the full HL-LHC data and at FCC-hh.

Speaker: Zhuoni Qian (DESY)

EPS_202107.pdf

T10: Searches for New Physics: Part 2

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Marija Vranjes Milosavljevic (Institute of Physics Belgrade)

144 Search for invisible decays at BESIII

BESIII has collected 448.2 M $\psi(3686)$ data set and 10 B $J/\psi$ data set. The huge clean data sample provide an excellent chance to search for new physics. We report the search for decay $J/\psi\to\gamma + invisible$, which is predicted by next-to-minimal supersymmetric model. Without significant signal found, we gave around 6.2 times better upper limits than previous CLEO-c’s results. In addition, we report the preliminary result of the first search for the invisible decay of $\Lambda$. This invisible decay is predicted by the mirror matter model which could explain the $4\sigma$ discrepancy in neutron lifetime measurement results from the beam method and bottle method.

Speaker: Xiaodong Shi (Shandong University)

XDTalk.pdf

145 Searches for additional Higgs bosons at CMS

Recent searches for BSM Higgses (both neutral and charged) performed by the CMS experiment at a center of mass of 13 TeV will be presented.

Speaker: Mariarosaria D'Alfonso (Massachusetts Inst. of Technology (US))

dalfonso_EPS_july26.pdf

146 Searches for additional Higgs bosons at ATLAS

The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable to solely explain some observations. Many extensions addressing such shortcomings introduce additional Higgs-like bosons which can be either neutral, singly-charged or even doubly-charged, or additional resonances with masses larger or smaller than that of the SM Higgs boson. The current status of searches for these particles based on the full LHC Run 2 dataset of the ATLAS experiment at 13 TeV are presented.

Speaker: Maria Florencia Daneri (Buenos Aires)

EPS2021_Daneri.pdf

147 ATLAS Searches for Resonances Decaying to Boson Pairs

Many extensions to the Standard Model predicts new particles decaying into two bosons (W, Z, photon, or Higgs bosons) making these important signatures in the search for new physics. Searches for such diboson resonances have been performed in final states with different numbers of leptons, photons, as well as jets and b-jets where new jet substructure techniques are used to disentangle the hadronic decay products in highly boosted configuration. This talk summarises recent ATLAS searches with Run 2 data collected at the LHC and explains the experimental methods used, including vector- and Higgs-boson-tagging techniques.

Speaker: Nora Emilia Pettersson (CERN)

20210726_DibsonSearches.pdf

148 Searches for heavy resonances decaying into Z, W, and Higgs bosons at CMS

We present a summary of searches for new heavy resonances decaying into pairs or triplets of bosons, performed on proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV. A common feature of these searches is the boosted topology, where the decay products of the considered bosons (both electroweak W, Z bosons and the Higgs boson) are expected to be highly energetic and close in angle. In cases with hadronic boson decays this leads to massive, large radius jets with substructure. The exploitation of jet substructure techniques (with deep neural networks and others), allows to increase the sensitivity of such searches. Techniques to calibrate such jets discriminant and to estimate total background in data are used. Results are interpreted in the context of multiple scenarios beyond the standard model.

Speaker: Cheng Chen (Peking)

EPS2021_chengchen.pdf

149 Searches for exotic decays of the Higgs boson with the ATLAS detector

Exotic decays of the Higgs boson provide a unique window for the discovery of new physics, as the Higgs boson may couple to hidden-sector states that do not interact under the Standard Model gauge transformations. Models predicting exotic Higgs boson decays to pseudoscalars can explain the galactic centre gamma-ray excess, if the additional pseudoscalar acts as the dark matter mediator. In addition, theories beyond the Standard Model may predict lepton-flavor violating (LFV) decays of the Higgs boson. This talk presents recent ATLAS searches for decays of the 125 GeV Higgs boson to new particles, and searches for LFV decays of the Higgs boson. These searches use LHC collision data at sqrt(s) = 13 TeV collected by the ATLAS experiment in Run 2.

Speaker: Benjamin Nachman (ATLAS (LHC Experiment ATLAS))

EPSJuly2021.pdf

150 Searches for Higgs exotic decays and additional (pseudo)scalars at CMS

Recent CMS searches for additional scalars (pp->a, Maaa) will be presented.

Speaker: Antoine Lesauvage (Centre National de la Recherche Scientifique (FR))

EPS_ExoticHiggsDecaysCMS_AntoineLesauvage.pdf

151 The forgotten channels: charged Higgs boson decays to a $W^\pm$ and a non-SM-like Higgs boson

The presence of charged Higgs bosons is a generic prediction of multiplet extensions of the Standard Model (SM) Higgs sector. Focusing on the Two-Higgs-Doublet-Model (2HDM), we discuss the charged Higgs boson collider phenomenology in the theoretically and experimentally viable parameter space. While almost all existing experimental searches at the LHC target the fermionic decays of charged Higgs bosons, we point out that the bosonic decay channels --- especially the decay into a non-SM-like Higgs boson and a $W$ boson --- often dominate over the fermionic channels. We propose several benchmark scenarios with distinct phenomenological features in order to facilitate the design of dedicated LHC searches for charged Higgs bosons decaying into a $W$ boson and a non-SM-like Higgs boson.

Speaker: Jonas Wittbrodt (Lund University)

wittbrodt.pdf

T12: Detector R&D and Data Handling: Miscellaneous

Conveners: Annika Vauth (Universität Hamburg), Vincent Boudry (LLR – École polytechnique)

152 Detector Challenges of the strong-field QED experiment LUXE at the European XFEL

The LUXE experiment aims at studying high-field QED in electron-laser and photon-laser interactions, with the 16.5 GeV electron beam of the European XFEL and a laser beam with power of up to 350 TW. The experiment will measure the spectra of electrons and photons in non-linear Compton scattering where production rates in excess of 109 are expected per 1 Hz bunch crossing. At the same time positrons from pair creation in either the two-step trident process or the Breit-Wheeler process will be measured, where the expected rates range from 10^-3 to 10^3 per bunch crossing, depending on the laser power and focus. These measurements have to be performed in the presence of low-energy high radiation-background. To meet these challenges, for high-rate electron and photon fluxes, the experiment will use Cherenkov radiation detectors, scintillator screens, sapphire sensors as well as lead-glass monitors for backscattering off the beam-dump. A four-layer silicon-pixel tracker and a compact electromagnetic tungsten calorimeter with GaAs sensors will be used to measure the positron spectra. The layout of the experiment and the expected performance under the harsh radiation conditions will be presented.

Speaker: Oleksandr Borysov (DESY)

luxe_det_eps2021_ob.pdf

153 The ESS Neutrino Super-Beam Near Detector

The ESS Neutrino Super-Beam (ESSnuSB) is a proposed long-baseline neutrino oscillation experiment, performed with a high-intensity neutrino beam, to be developed as an extension to the European Spallation Source proton linac currently under construction in Lund, Sweden. The neutrinos would be detected with the near and far detectors of the experiment, the former within several hundred meters of the neutrino production point and the latter within several hundred kilometers. The far detector will consist of a megaton-scale water-Cherenkov detector, and the near detector will consist of a kiloton-scale water-Cherenkov detector in combination with a fine-grained tracking detector and an emulsion detector. The purpose of the near detector is to constrain the flux of the neutrino beam as well as extract the electron-neutrino interaction cross-section in water, thus requiring well performing energy reconstruction and particle flavor identification techniques. These measurements are crucial for the neutrino oscillation study that will be conducted using the far detector.

Year 2021 sees the finalization of the conceptual design of the near detector through a study of the performance of a number of different design options, and a characterization of the neutrino reconstruction and flavor identification performances. In this talk we report on these studies.

Speaker: Dr Alexander Burgman (Lund University)

ABurgman_ESSnuSBND_210726_EPSHEP2021_v02.pdf

154 The DUNE Near Detector

The Deep Underground Neutrino Experiment (DUNE) is an upcoming long-baseline neutrino experiment which will study neutrino oscillations. Neutrino oscillations will detected at the DUNE far detector 1300 km away from the start of the beam at Fermilab. The DUNE near detector (ND) will be located on-site at Fermilab, and will be used to provide an initial characterization of the neutrino beam, as well as to constrain systematic uncertainties on neutrino oscillation measurements. The detector suite consists of a modular 50-ton LArTPC (ND-LAr), a magnetized 1-ton gaseous argon time projection chamber (ND-Gar) surrounded by an  electromagnetic calorimeter, and the System for on-Axis Neutrino Detection (SAND), composed by magnetized electromagnetic calorimeter and inner tracker. In this talk, these detectors and their physics goals will be discussed.

Speaker: Andrew Mastbaum (Rutgers University)

20210726_dune-nd-epshep.pdf

155 Performances of a 3D optical readout TPC for the CYGNO experiment

Gaseous Time Projection Chambers (TPC) with optical readout are an innovative and very promising detection technique to enhance the the sensitivity for light dark matter candidates.

The Cygno experiment is pursuing this technique by developing a TPC operated with gas mixtures at atmospheric pressure equipped with a Gas Electron Multipliers (GEM) amplification stage that produces visible light. Light is collected by as high sensitivity and resolution scientific CMOS camera, while a fast photodetector is used to measure the drift time of the primary ionisation electrons and thus reconstruct the third coordinate of the ionisation track.

In this contribution, we illustrate the technical solutions developed to construct detector prototypes and discuss their performances when exposed to radioactive sources. We present results in terms of electroluminescence yield and charge gain when operated with several gas mixtures based on He-CF4, He-CF4-isobutane, Ar-CF4, and different electric field configurations. We also illustrated the solutions adopted for the DAQ and trigger systems and the performances of an innovative multi-stage pattern recognition algorithm based on advanced clustering techniques. We show how such solutions are essential to identify and select interesting events and how we plan to have them online to cope with the data throughput. Finally, we show the evolution of the project from small size detectors to the current 50 litres prototype which will be installed and tested underground at LNGS this year. A 1 cubic meter demonstrator is expected to be built in 2021/22 and subsequently installed and commissioned at LNGS aiming at a large scale apparatus in a later stage.

Speaker: andrea messina (University of Rome, Sapienza and INFN)

Cygno-messina-EPS2021.pdf

156 Detector characterization for Legend-200 experiment

The LEGEND collaboration is developing an experimental search for the neutrinoless double-beta ( $0\nu\beta\beta$) decay of the $^{76}$Ge isotope.
Its first phase, LEGEND-200, uses 200 kg of $^{76}$Ge-enriched high-purity germanium (HPGe) detectors in an active liquid argon shield and is currently under construction at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy.
Inverted coaxial point-contact (ICPC) detectors are deployed in the experiment. Their peculiar geometry provides an excellent energy resolution in a broad energy range and impressive discrimination of signal against background events.
LEGEND’s search for $0\nu\beta\beta$ requires a precise understanding of the behavior of germanium detectors, requiring extensive detector characterization.
The acceptance tests aim to verify the performance of the delivered detectors meets specifications and to determine their optimal operational parameters.
This talk will provide a review and the first results of the detector characterization program.

Speaker: Valentina Biancacci (Università degli Studi di Padova & INFN Padova)

Detector_characterization_for_Legend-200_VBiancacci_260721.pdf

157 TES Detector for ALPS II

The Any Light Particle Search II (ALPS II) is a light-shining-through-a-wall (LSW) experiment at DESY, Hamburg, attempting to detect axions and axion-like-particles (ALPs), which can comprise dark matter and solve long-standing problems in physics. ALPS II can convert photons into axions/ALPs in the presence of a magnetic field, in an optical cavity. After passing through an opaque, light-tight barrier, these particles can reconvert to photons in another optical cavity, and be detected. The detection requires a sensor capable of observing the extremely low regenerated photon rates of $\mathcal{O}(10^{-5})$ Hz, necessitating a very low dark rate and high detection efficiency. This can be achieved by using a TES, a Transition Edge Sensor, a cryogenic calorimeter exploiting the drastic temperature dependence of a material's electrical resistance in its transition region around 140 mK. To achieve this, the setup is housed in a dilution refrigerator cooling it down to a temperature of $<25$ mK. Being sensitive to low-energy 1064 nm photons also makes the detector susceptible to other particles and backgrounds which can hamper the targeted low dark rate.

We present the setup of the TES detector for ALPS II, its current status, and the analysis of its backgrounds and further improvements in the cryogenic environment to reduce the backgrounds. The viability and outlook of such a detector for the ALPS II experiment will be discussed, including future steps to measure the detection efficiency, etc.

Speaker: Rikhav Shah (ALPS (ALPS _ Any Light Particle Search))

TES_Talk_RShah_EPS.pdf

158 New Results from the Silicon Vertex Detector of the Belle II Experiment

The Silicon Vertex Detector (SVD) consists of four layers of double-sided silicon strip sensors. The SVD is one of the two vertex subdetectors within Belle II.
Since the start of data taking in 2019 at the Super-KEKB collider (KEK, Japan), which has the highest peak-luminosity ever recorded, the SVD is operated reliably and with high efficiency, despite exposure to harsh beam background.
Measurements using data show that the SVD has both high signal-to-noise ratio and hit efficiency, as well precise spatial resolution. Further these properties are stable over time. Recently the simulation has been tuned, using data, to improve the agrement between data and MC for cluster properties.
The good hit-time resolution can be exploited to further improve the robustness against the higher levels of background expected as the instantaneous luminosity increases in the next years of running. First effects of radiation damage on strip noise, sensor currents and depletion voltage have been measured, although they do not have any detrimental effect on the performance of the detector.

Speaker: Luigi Corona (BELLE (BELLE II Experiment))

20210726_EPS_Luigi_Corona.pdf

159 The operation and performance of the TOP detector at the Belle II experiment

The SuperKEKB/Belle II experiment, the successor of the former KEKB/Belle experiment at KEK, has started its physics data taking with the full detector system since March 2019. The Time-of-Propagation (TOP) detector was designed and integrated into the Belle II detector for particle identification in the barrel region. The TOP detector consists of quartz radiators and photodetectors, Micro-Channel-Plate (MCP) PMT, and reconstructs a ring image of Cherenkov photons generated by an incident particle. It measures the timing of each detected photon with an accuracy of less than $100~\mathrm{ps}$ for good $K/\pi$ separation.

In the operation of the TOP detector, harsh beam-induced background in the high luminosity environment is one of the critical issues to achieve high performance. We have developed various tools to visualize MCP-PMT performance and to identify and fix errors arising from front-end electronics during data taking. The TOP detector provides 85% $K$ efficiency at a 10% $\pi$ misidentification rate in the data at the early stage of the experiment. In this talk, we will report the operation status and the performance by the summer of 2021.

Speaker: Kazuki Kojima (BELLE (BELLE II Experiment))

EPS-HEP2021TOPKojimaFinal_mainSlides.pdf

16:15 Break

T01: Astroparticle and Gravitational Waves: Part 3

160 Southern Wide-field Gamma-ray Observatory: status and prospects

The Southern Wide Field Gamma-ray Observatory (SWGO) is an international R&D project aiming to design and prototype a wide field-of-view gamma-ray facility to monitor the Southern Hemisphere sky in gamma-rays.

SWGO will be placed at a high altitude (above 4.4 km) in South America and aims to provide a good sensitivity for observations from the low energies (~100 GeV) up to the PeV region. Such energy range allows covering a broad physics program, being entirely complementary to the Cherenkov Telescope Array (CTA) and other Northern ground-based observatories, such as HAWC or LHAASO.

In this talk, I will present the current status and plans for SWGO, namely, progress on the detector design concepts being evaluated, array layout options and site procurement. The expected sensitivity of SWGO and its science capabilities will also be addressed.

Speaker: Ruben Conceição (LIP - Laboratório de Instrumentação e Física Experimental de Partículas)

Conceicao_SWGO_EPS-HEP21.pdf

161 Ultra-high-energy cosmic rays from star-forming galaxies constrain the extragalactic magnetic field

The Pierre Auger Observatory (PAO) has recently detected significant correlations between the arrival directions of ultra-high-energy cosmic rays (UHECRs) and positions in the sky of local star-forming galaxies. We interpret these results in terms of the local density of sources and the magnetic fields governing the UHECR propagation [1]. We determine the level of UHECR deflections for an ensemble of sources in a random extragalactic magnetic field description as well as a Galactic magnetic field model. In addition, we take into account energy losses with background photon fields as well as spectrum and composition measurements by the PAO. We find that the PAO anisotropy measurement is consistent with large extragalactic magnetic field strengths ($B > 0.6$ nG for a coherence length of 1 Mpc at the $5\sigma$ confidence level) in the case of a local density of star-forming galaxies. Larger source densities, on the other hand, allow for weaker extragalactic magnetic fields. However, the acceleration of UHECRs by such abundant sources is more challenging to motivate. Too large source densities and extragalactic magnetic field strengths decrease the expected level of anisotropy and are, therefore, disfavoured as well. This translates to upper limits of $B < 24 \ \rm nG$ and $\rho_0 < 9.0 \cdot 10^{-2} \ \rm Mpc^{-3}$ at the 90% confidence level.

---

[1] A. van Vliet, A. Palladino, A. Taylor and W. Winter, arXiv:2104.05732.

Speaker: Dr Arjen van Vliet (DESY Zeuthen)

VanVliet_EGMFConstraintsFromUHECRCorrelationsWithStarFormingGalaxies.pdf

162 Jet-induced high-energy neutrino and electromagnetic counterparts of supermassive black hole mergers

Supermassive black hole (SMBH) coalescences are ubiquitous in the history of the Universe and often exhibit strong accretion activities and powerful jets. These SMBH mergers are also promising candidates for future gravitational wave detectors such as Laser Space Inteferometric Antenna (LISA). In this work, we investigate the neutrino and electromagnetic counterpart emissions originating from the jet-induced shocks. We formulate the jet structures and relevant interactions therein, and then evaluate neutrino emission from each shock site. We find that month-to-year high-energy neutrino emission from the postmerger jet after the gravitational wave event is detectable by IceCube-Gen2 within approximately five to ten years of operation in optimistic cases where the cosmic-ray loading is sufficiently high and a mildly super-Eddington accretion is achieved. In addition, based on our model that predicts slowly fading transients with durations of ∼1−10 months with a time delay from days to months after the coalescence, we discuss implications for EM follow-up observations after the GW detection.

Speaker: Mr Chengchao Yuan (Pennsylvania State University)

163 Very high energy observations of GRBs

Gamma-ray bursts (GRBs) are transient events releasing a large amount of energy in a short amount of time as electromagnetic radiation. In the past decades, both observational and theoretical efforts were made to understand their inner workings, both in the prompt and afterglow phase. The origin of the GeV emission detected by Fermi-LAT in several GRBs is one of the aspects of GRB physics which is currently not well understood. Observations at very high energies (VHE, E>100 GeV) by Cherenkov telescopes, given their better sensitivity, can provide crucial information to understand the mechanisms behind such high energy components. After almost 15 years of efforts, the MAGIC and H.E.S.S. collaborations finally detected their first bursts, GRB190114C and GRB180720B respectively, opening a new era in the study of GRBs. Such detections proved the presence of a new additional emission component up to TeV energies in the GRB afterglow phase, which can be explained by the synchrotron self-Compton process. Other two GRBs were also detected, GRB190829A by H.E.S.S. and GRB201216C by MAGIC, bringing more information but also revealing a complex picture to explain the origin of the VHE emission. In this context, observations by future facilities as the Cherenkov Telescope Array (CTA) observatory will play a crucial role to increase our understanding of the VHE emission in GRBs. In this contribution I will present the outstanding results accomplished in the last years by Cherenkov telescopes in the observation of GRBs and provide an overview of what can be achieved with future instruments.

Speaker: Alessio Berti (Max Planck Institute for Physics)

berti_GRBs_VHE_EPS_HEP_20210726.pdf

17:40 Break & Open Discussion

164 Unveiling the origin of steep decay in $\gamma$-ray bursts

γ-ray bursts (GRBs) are transient cataclysmic events, whose role became central in the new multi-messenger era. In the present work I propose a novel investigation of the GRB emission mechanism, via time-resolved spectral analysis of the X-ray tails of bright GRB pulses observed with the XRT instrument onboard the Neil Gehrels Swift Observatory, discovering a unique relation between the spectral index and the flux. The investigation of the spectral evolution during the GRB tail is an ideal diagnostic to understand the connection between the emission processes, the cooling processes and the outflow environment. I thoroughly discuss possible interpretations in relation to current available models and I show the incompatibility of our results with the standard high latitude emission. Our results for the first time strongly suggest evidence of adiabatic cooling of the emitting particles, shedding light on fundamental physics of relativistic outflows in GRBs. Finally I discuss the crucial role of future wide-field X-ray telescopes, such as the mission concept Theseus, for the characterisation of the GRB tail emission, highlighting also its importance in the multi-messenger context.

Speaker: Samuele Ronchini

EPS.pdf

165 CALET on the International Space Station: a precise measurement of the iron spectrum

The Calorimetric Electron Telescope (CALET) was launched on the International Space Station in 2015 and since then has collected a large sample of cosmic-ray charged particles over a wide energy. Thanks to a couple of layers of segmented plastic scintillators placed on top of the detector, the instrument is able to identify the charge of individual elements from proton to iron (and above).
The imaging tungsten scintillating fiber calorimeter provides accurate particle tracking and the lead tungstate homogeneous calorimeter can measure the energy with a wide dynamic range. One of the CALET scientific objectives is to measure the energy spectra of cosmic rays, to shed light on their acceleration and propagation in the Galaxy. After five years of observation, a precise measurement of the iron spectrum is now available in the range of kinetic energy per nucleon from 10 GeV/n to 2 TeV/n. The CALET result will be reported and compared with the findings from other experiments. A description of the analysis and details on the systematic uncertainties will be given.

Speaker: Dr Caterina Checchia (University of Siena)

CHECCHIA_EPS2021.pdf

T03: Dark Matter: Part 3

Conveners: Belina von Krosigk (Universität Hamburg), Elisabetta Baracchini (Gran Sasso Science Institute)

166 CYGNUS – Directional Identification of Nuclear and Electron Recoils from Dark Matter and Solar Neutrinos

Recent advances in development of gaseous Time Projection Chambers (TPCs) with ability to reconstruct the direction of ionisation tracks at low energy, opens the possibility of building a nuclear recoil observatory capable of detecting directional signals from WIMP dark matter and coherent elastic neutrino-nucleus scattering (CEvNS) events from solar neutrinos. CYGNUS aims to achieve this through construction of an array of large-scale TPCs, distributed in multiple deep underground laboratories at different latitudes with multiple target nuclei, including He, C, F and S. Such an observatory would allow sensitivity to WIMP-nucleon scattering below the so-called neutrino floor, would open a new window on solar neutrino physics in channels so-far unexplored, and allow exploration of new Beyond the Standard Model (BSM) physics. Simultaneous reconstruction of low energy electron recoil tracks is also feasible to enhance background discrimination but also to open further channels for exploration. With CYGNUS we can envisage a definitive confirmation of the galactic origin of WIMPs and eventually mapping of the local velocity distribution even to low WIMP mass. Smaller pathfinder detectors, backed by simulations of directional sensitivity and background discrimination power, are now being developed and run to allow optimisation of the technologies and the cost-effectiveness of CYGNUS. These devices can nevertheless contribute short-term physics goals, for instance observation of the Migdal effect. Progress towards realisation of CYGNUS, its potential sensitivity in different scenarios, and results of recent R&D will be outlined, including discussion of new results on operation with SF6 negative ion gas with novel charge readout systems designed to achieve directional sensitivity to low mass WIMPs.

Speaker: Lindsey Bignell (The Australian National University)

Cygnus_EPS-HEP.pdf

167 The Cygno Experiment

The detection of ultra-rare events as the interaction of galactic dark matter (DM) candidate particles or of neutrinos originated from the Sun requires the development of innovative detection techniques. In particular future experiments for direct DM detection requires to extend their sensitivity to masses well below 10 GeV.

The Cygno collaboration plans to build and operate at LNGS a cubic meter demonstrator of a gaseous time projection chamber (TPC), equipped with an optical readout and using a He:CF4 gas mixture kept at atmospheric pressure. The presence of low Z atoms allows to reach a competitive sensitivity to DM masses in the GeV range while the presence of fluorine can be used to set limits on a spin-dependent DM interaction cross-section.

The Cygno TPC is equipped with a Gas Electron Multipliers (GEM) amplification stage of the primary ionization electrons. Light is produced from the GEM while scientific CMOS cameras and fast photodetectors are combined to obtaining a three-dimensional reconstruction of the tracks either due to nuclear or to electron recoils.
The design and the sensitivity of the demonstrator based on advanced Monte Carlo simulations of the radioactivity of the materials and of the LNGS cavern are reported. Pattern recognition algorithms are used to evaluate the identification capability of nuclear recoils against electronic recoils and studied in data from small scale prototypes. Energy measurement and also sensitivity to the source directionality are also evaluated. Therefore, a Cygno TPC would also be able to detect electron recoils originated by solar neutrinos interactions.
The Cygno collaboration plans to demonstrate the scalability of such detector concept to reach a target mass large enough to significantly extend our knowledge about DM nature and solar neutrinos.

Speaker: Gianluca Cavoto (Sapienza Universita e INFN, Roma I (IT))

CYGNO EPS 2021.pdf

168 Supernova signals of light dark matter

By virtue of their high temperatures, supernovae can produce large fluxes of MeV-scale dark matter even at couplings stronger than those constrained by cooling. In this region of parameter space, the dark matter can become diffusively trapped by scatterings within the protoneutron star, ultimately escaping with semirelativistic velocity. I will show that this can lead to the formation of a diffuse Galactic flux of supernova-produced dark matter. Furthermore, I will show that this population’s high velocity compensates for its low mass and allows it to be detected in direct detection experiments designed for GeV-scale WIMPs. I will conclude with a discussion of the potential to discriminate this dark matter from a cosmological abundance of WIMPs using directionality.

Speaker: William DeRocco (Stanford University)

EPS_HEP_2021.pdf

169 Direct detection of non-galactic light dark matter

A fraction of the dark matter in the solar neighborhood might be composed of non-galactic particles with speeds larger than the escape velocity of the Milky Way. The non-galactic dark matter flux would enhance the sensitivity of direct detection experiments, due to the larger momentum transfer to the target.

In this note, we calculate the impact of the dark matter flux from the Local Group and the Virgo Supercluster diffuse components in nuclear and electron recoil experiments. The enhancement in the signal rate can be very significant, especially for experiments searching for dark matter induced electron recoils.

Speaker: Gonzalo Herrera (Technical University of Munich, Max-Planck Institute for Physics)

Direct_detection_of_non_galactic_light_dark_matter_TALK_EPS.pdf

170 eV-threshold Direct Dark Matter Searches

Over the last decade, significant advancements in semiconductor charge detectors have enabled single-electron resolution and threshold for the first time. These low thresholds significantly enhance detector resolution to well-motivated, but unconstrained, sub-GeV dark matter models. Following an overview of these experimental techniques in silicon and germanium detectors, I will focus on one such detector technology: Skipper CCDs. I will summarize the robust CCD program over the next decade, including recent results from DAMIC at SNOLAB, upcoming experiments including SENSEI and DAMIC-M, and ultimately the 10 kg scale OSCURA detector.

Speaker: Daniel Baxter (University of Chicago)

EPS_07262021.pdf

171 Status and Plans of SuperCDMS SNOLAB

SuperCDMS SNOLAB is an underground cryogenic experiment currently under construction. The main objective of the experiment is a search for dark matter particles with masses < 10 GeV. Electron or nuclear recoils deposit energy in the germanium and silicon crystals which is collected via phonon and charge sensors. Two different detector designs are utilized: HV(High Voltage) and iZIP(interleaved Z-dependent Ionization and Phonon) detectors. HV detectors with a low threshold and excellent energy resolution will probe dark matter in the sub-GeV range; iZIP detectors, benefiting from their good separation power between electron and nuclear recoil events, are optimized to detect dark matter masses above 3 GeV. An initial HV detector is currently hosted at CUTE, a SNOLAB cryogenic test facility, with plans to take science data in the immediate future.

Speaker: Yan Liu (UBC)

EPS-HEP2021_YL_v3.pdf

T04: Neutrino Physics: CP-violation and neutrinos

Convener: Stefania Bordoni (Université de Genève)

172 T2K status and plans

Tokai-to-Kamioka (T2K) is a long baseline neutrino experiment which uses the proton beam at the Japan Particle Accelerator Research Centre (JPARC) to produce a beam of muon neutrinos and antineutrinos. T2K determines neutrino oscillation parameters of interest by comparing the measured neutrino rate and spectrum at a near detector complex, located at JPARC, and at Super-Kamiokande, a water-Cherenkov detector, located 295 km away.

The T2K experiment performs world-leading measurements of the PMNS oscillation parameters \Delta_m^{2}{32}, sin^2(\theta{23}) and the CP violating phase \delta_{CP}, providing an exclusion at 3$\sigma$ for some values of this parameter.

T2K is now undergoing major improvements and refurbishment. The Super-Kamiokande detector has been loaded with 0.02% of Gadolinium in 2020, enabling enhanced neutron tagging. An upgrade of the ND280 near detector, located 2.5 degrees off-axis, is scheduled for installation in 2022. The WAGASCI near detector, installed in 2018 and located 1.5 degrees off-axis, is also collecting statistics and a joint analysis at different off-axis angles is being prepared.

The T2K collaboration is working on an updated oscillation analysis to improve the control of systematic uncertainties and enable future inclusion of improved near and far detector data. A new beam tuning has been developed, based on an improved NA61/SHINE measurement which used a replica of the T2K target and which includes a refined modeling of the materials in the beam line. New selections have been developed as well; ND280 selections now include proton and photon tagging, and the muon-neutrino samples at Super-Kamiokande now includes pion tagging. The collaboration has also developed a more robust model of systematic uncertainties for the nuclear effects in neutrino-nucleus interactions, notably for the Spectral Function approach and for pion tagging.

This talk will review the latest measurements of oscillation parameters from T2K, the status of the new selection and systematic developments and the plans for upcoming data runs from T2K.

Speaker: Stephen Dolan

SDolanTalk_EPSHEPv2.pdf

173 Latest 3-flavor neutrino oscillations results from the NOvA experiment

NOvA is a long-baseline neutrino oscillation experiment. Its large tracking calorimeters can detect and identify muon and electron neutrino interactions with high efficiency. Neutrinos produced by the NuMI beam are detected by a Near Detector, located at Fermilab, and a much larger Far Detector, located 810km away in Ash River, Minnesota. NOvA can measure the electron neutrino and antineutrino appearance rates, as well as the muon neutrino and antineutrino disappearance rates, in order to constrain neutrino oscillations parameters, including the neutrino mass hierarchy and the CP-violating phase $\delta_{CP}$.
This talk will present NOvA's latest results combining both neutrino data ($13.6\times10^{20}$POT) and antineutrino data ($12.5\times10^{20}$ POT).

Speaker: Steven Calvez (Colorado State University)

calvez_eps_hep_2021.pdf

174 Hyper-Kamiokande experiment

The Hyper-Kamiokande experiment consists of a 260 kt underground water Cherenkov detector with a fiducial volume more than 8 times larger than that of Super-Kamiokande. It will serve both as a far detector of a long-baseline neutrino experiment and an observatory for astrophysical
neutrinos and rare decays.

The long-baseline neutrino experiment will detect neutrinos originating from the upgraded 1.3 MW neutrino beam produced at the J-PARC accelerator 295 km away. A near detector suite, close to the accelerator, will help characterise the beam and minimise systematic errors.

The experiment will investigate neutrino oscillation phenomena (including CP-violation and mass ordering) by studying accelerator, solar and atmospheric neutrinos, neutrino astronomy (solar, supernova, supernova relic neutrinos) and nucleon decays.

In this talk, we will present an overview of the Hyper-Kamiokande experiment, its current status and physics sensitivity.

Speaker: Takuya Tashiro

2021EPS_HK_tashiro_v1.pdf

175 DUNE The Deep Underground Neutrino Experiment

The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino experiment. Its main physics goals are the precise measurement of the neutrino oscillation parameters, in particular the violation of the charge-parity symmetry and the neutrino mass hierarchy, measuring proton decay and BSM physics searches. DUNE consists of a Far Detector (FD) complex with four multi-kiloton liquid argon detectors, and a Near Detector (ND) complex located close to the neutrino source at Fermilab (USA). Here we present an overview of the DUNE experiment, its detectors, and physics capabilities.

Speaker: Djurcic Zelimir

Djurcic_EPS_2021_s.pdf

176 The ESSnuSB/HIFI Design Study

The ESS 5 Megawatt linac will be the world’s most powerful accelerator, enabling with its 1016 2 GeV protons per second the production of the world’s most intense flux, not only of neutrons, but also of neutrinos and muons. This opens unique opportunities for High Intensity Frontier fundamental physics. An EU supported Design Study of an ESS neutrino Super Beam (ESSnuSB) is under way since 2018 with the participation of physicists from 15 European institutions of the use of the neutrino beam for long baseline neutrino oscillations. Within this study is being designed the upgrade of the linac required to increase its power to 10 MW by the provision of extra H- pulses between the proton linac pulses, of a ca 400 circumference accumulator ring to compress the 3ms long linac pulses to 1.3µs, of a set of four high power neutrino targets with focusing horns and a kiloton near and a megaton far water Cherenkov neutrino detector, the latter at a distance of 540 km at the location of the second neutrino oscillation maximum. The publication of the ESSnuSB Design Study report is approaching and highlights among achieved design results will be presented. More recently a study of the use of the intense muon flux produced together with neutrinos has been started, aiming at a design of, in the first stage, a Muon Cooling Test Facility to be followed by the study of a nuSTORM low-energy facilty, a Neutrino Factory and ultimately a Muon Collider Higgs Factory. The plan for this High Intensity Frontier Initiative (HIFI) design work will be presented.

Speaker: Loris D'Alessi

20210726_DAlessi_ESSnuSB-HIFI_EPS-HEP2021.pdf

177 On the sources of CP violation in the Lepton sector

The phenomenon of Neutrino Oscillation has been very well confirmed by a plethora of data; we are now entering a precision era in which the mixing angles and mass differences are going to be measured with unprecedented precision by ongoing and planned experiments. However, the new measurements could reveal that the standard three flavor scenario is not enough for a complete description of oscillations and a new paradigm beyond the standard physics in the lepton sector must be invoked.
In this talk I will discuss how to test that all CP violating asymmetries are described in terms of the single leptonic Jarlskog invariant as predicted in the absence of new physics effects.

Speaker: Davide Meloni (Mathematics and Physics Department, Roma Tre University)

meloni.odp

meloni.pdf

T05: Heavy Ion Physics: Part 3

Note: All contributions are given 12 minutes + 3 min for questions

178 Measurements of mixed harmonic cumulants in Pb-Pb collisions at 5.02 TeV with ALICE

Multi-particle cumulants of azimuthal angle correlations are compelling tools to constrain the initial conditions and probe the properties of the quark-gluon plasma created in the ultrarelativistic heavy-ion collisions at the LHC. However, only very few of them have been measured experimentally and supplemented with corresponding theoretical calculations.

Using a newly developed correlation technique, we will present the first measurements of mixed harmonic cumulants in Pb--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$~TeV recorded with the ALICE detector. The centrality dependence of correlations between two flow coefficients as well as the correlations between three flow coefficients, both in terms of their second moments, are shown. In addition, a collection of mixed harmonic cumulants involving higher moments of flow amplitudes $v_2$ and $v_3$ is measured for the first time, where the characteristic signature of negative, positive and negative signs for the four-, six- and eight-particle cumulants, respectively, is observed. The measurements are compared to the hydrodynamic calculations using iEBE-VISHNU with AMPT and TRENTo initial conditions. It is shown that these new studies on correlations between three flow coefficients as well as correlations between higher moments of two different flow coefficients can tighten constraints on initial-state models and help extract precise information on the dynamic evolution of the hot and dense matter created in heavy-ion collisions at the LHC.

Speaker: You Zhou (Niels Bohr Institute)

YZ_EPSHEP_9.pdf

179 Search for collective behaviour and multiparton interactions in ep scattering at HERA

Collective behaviour of final-state hadrons is studied in ep scattering using the H1 and ZEUS detectors at HERA. Measurements of two- and four-particle azimuthal correlations in both DIS and photoproduction are presented. Ridge yields are extracted from fits to two-particle correlations with H1 data. Comparisons of the magnitudes and signs of the first- and second-harmonic of two-particle correlations are made with ZEUS data. Four-particle cumulant correlations are observed to be positive.
The results do not indicate the kind of collective behaviour observed at RHIC and the LHC in high-multiplicity hadronic collisions. The possibility of multiparton interactions are studied in photoproduction with ZEUS. Comparisons of PYTHIA predictions with the measurements strongly indicate the presence of multiparton interactions from hadronic fluctuations of the exchanged photon.

Speaker: Dhevan Gangadharan (Universitat Heidelberg)

EPS2021_Dhevan.pdf

180 Measurements of collective behavior in pp, Xe+Xe, and Pb+Pb collisions with the ATLAS detector

This talk presents ATLAS measurements of collective, flow phenomena in a variety of collision systems, including pp collisions at 13 TeV, Xe+Xe collisions at 5.44 TeV, and Pb+Pb collisions at 5.02 TeV. A new measurement of vn-[pT] correlations in Xe+Xe and Pb+Pb collisions is presented for harmonics n=2, 3, and 4. The correlation between the event-wise average transverse momentum ([pT]) and the harmonic flow (vn) carries important information about the initial-state geometry of the Quark-Gluon Plasma. Additionally, the potential quadrupole deformation in Xe+Xe is predicted to produce an initial state with enhanced shape and size fluctuations, and result in non-trivial change in the correlation. A measurement of the sensitivity of two-particle correlations in pp collisions to the presence of jets is presented. By rejecting particles associated with low-pT jets, this data can distinguish the role that semi-hard processes play in the collective phenomena observed in pp collisions.

Speaker: Somadutta Bhatta

EPSHEP2021.pptx

EPSHEP2021_Somadutta_V3.pdf

181 Studies of anisotropic flow with event-shape engineering and mean transverse momentum - flow correlations in Pb-Pb, Xe-Xe and pp collisions with ALICE

Measurements of anisotropic flow ($v_n$) provide valuable information on the properties of the quark-gluon plasma.
Along with studies of standard flow observables, one can use strong fluctuations of the anisotropic flow for an efficient selection of the events corresponding to a specific initial geometry. Another quantity with unique sensitivity to physical processes in the initial state is the Pearson correlation coefficient of anisotropic flow and the mean transverse momentum, $\rho(v_{2}^{2},[p_{\rm T}])$. In particular, recent developments in heavy-ion theory suggest that initial momentum correlations and initial geometry give rise to dramatically different evolution of $\rho(v_{2}^{2},[p_{\rm T}])$ with charged-particle multiplicity, mainly at the lowest multiplicity region not accessible in most of the LHC experiments.

In this talk, the selection technique known as Event Shape Engineering has been used to measure the elliptic and triangular flow of inclusive and identified particles ($\pi$, K, p, ${\rm K}^{\rm 0}_{\rm S}$, $\Lambda$, $\Xi$) in Pb--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV recorded by the ALICE detector. The effect of the event-shape selection is within uncertainties independent of particle species up to $p_{\rm T} \sim 8$ GeV/$c$, and the origin of this observation is discussed. Next, we present the measurements of $\rho(v_{2}^{2},[p_{\rm T}])$ in Pb--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV and Xe--Xe collisions at $\sqrt{s_{\rm NN}} = 5.44$ TeV as a function of centrality, and as a function of charged-particle multiplicity at midrapidity that extends to the lowest multiplicities available. In addition, the results are complemented by the same measurements in pp collisions at $\sqrt{s} = 13$ TeV, where effects related to the initial geometry are suppressed. The measurements are compared to initial state models with and without initial momentum anisotropy and discussed in context of hydrodynamical and pQCD-inspired models. Finally, a new multi-harmonic correlation coefficient $\rho(v_{2}^{2},v_{3}^{2},[p_{\rm T}])$ is presented and discussed as an alternative to resolve between different initial state models in semicentral heavy-ion collisions.

Speaker: Emil Gorm Nielsen (ALICE)

EPS_slides_v6.pdf

182 Impact of the initial electromagnetic and glasma fields on heavy quarks and leptons from Z0 decay

Heavy quarks are excellent probes to study the initial stages of heavy ion collisions since they are generated in the early times around 0.1 fm/c together with a thermalization time that is comparable to the lifetime of the QGP phase. Ultra-relativistic heavy ion collisions are expected to generate a huge electromagnetic (e.m.) field that is expected to generate a splitting of the directed flow of charged particles and anti-particles. In this talk we will discuss how the strong initial e.m. field can lead to a large directed flow v1 of neutral particles/anti-particles D0 and anti-D0 of few percent much larger compared to the observed light charged particles v1 and how it can be considered as a possible probe of the formation of the quark-gluon plasma phase.
Moreover, we have found a general formula for all possible charge dependent flow observables that can be generated by the strong electromagnetic fields in non-central relativistic heavy ion collisions. The formula has a very simple form at pT larger than several GeV/c, which can be treated as the signature of charged dependent flow observables induced by e.m. fields. Furthermore, we found that the v1 splitting depends critically on the time evolution of the magnetic field. Based on this study, we finally discuss why the measurement of of leptons from Z0 decay and its correlation to the charmed mesons are better in probing e.m. fields and thus opening a new way to constrain the EM field.
The second topic we want to discuss is the evolution of HQ distribution in the initial glasma fields w.r.t. the standard HQs interaction with the QGP. From the interaction between glasma field and HQs, we find that the field can lead to an initial enhancement of RAA of charm quarks contrary to the pattern of the standard particle interaction; this furthermore leads to the modification on the relation between the elliptic flow v2 and RAA of charmed mesons after the interaction with the QGP. 
[1] Y. Sun, G. Coci, S. K. Das, S. Plumari, M. Ruggieri and V. Greco, Phys. Lett. B 798, 134933 (2019).
[2] Y. Sun, S. Plumari and V. Greco, Phys. Lett. B 816, 136271 (2021).
[3] Y. Sun, V. Greco and S. Plumari, arXiv: 2104.03742.
[4] L. Oliva, S. Plumari and V. Greco, arXiv: 2009.11066.
[5] S. K. Das, S. Plumari, S. Chatterjee, J. Alam, F. Scardina and V. Greco, Phys. Lett. B 768, 260-264 (2017).

Speaker: Dr Yifeng Sun (Department of Physics and Astronomy, University of Catania)

EPS-HEP.pdf

183 Polarization of lambda hyperons, vorticity and helicity structure in heavy-ion collisions

Simulations of peripheral Au+Au collisions at NICA energies was performed in the PHSD transport model. The properties of velocity and vorticity fields, hydrodynamic helicity was studied at different impact parameters and energies. The general structure of velocity field follows the "little bang" pattern which may be quantified by the velocity dependence allowing to extract the "Hubble" constant. Quadrupole structures of the vorticity field in transverse reaction plane was obtained. The effect of helicity separation was detected. Calculation of Λ - hyperons polarization is performed in thermodynamic and anomalous models at NICA energies. The polarization of Λ-hyperons at NICA energies was calculated in thermodynamic approximation and anomalous mechanism, based on Chiral Vortical Effect.

Speaker: Aleksei Zinchenko (P.G. Demidov Yaroslavl State University)

Talk-EPS-HEP-2021-Zinchenko.pdf

184 Spectator induced electromagnetic effects on charged meson production in nucleus-nucleus collisions from NA61/SHINE at CERN SPS

The SPS Heavy Ion and Neutrino Experiment (NA61/SHINE) studies the properties of hadron production in collisions of beam hadrons and nuclei with fixed hadronic and nuclear targets.
In this talk, I will discuss the space-time evolution of the system of strongly interacting matter created in the collision, studied from the modification of charged pion spectra and $\pi^{+}/\pi^{-}$ ratios by the electromagnetic (EM) field induced by the spectator system as a function of collision centrality. First results on Ar+Sc collisions at 40 A GeV/$c$ ($\sqrt{s_{NN}}$ = 8.76 GeV) will be shown, including the first-ever measurement of spectator induced EM effects in a small peripheral nucleus-nucleus system in the SPS energy range.
These will be compared to Ar+Sc intermediate collisions at 150 A GeV/$c$($\sqrt{s_{NN}}$ = 16.8 GeV) from NA61/SHINEs and Pb+Pb peripheral collision data at 158 A GeV/$c$ ($\sqrt{s_{NN}}$ = 17.3 GeV) obtained by the NA49 experiment at the CERN SPS. The present implications of the new data from NA61/SHINE for the space-time evolution of the system will be discussed.

Speaker: Sneha Bhosale (IFJ PAN)

SnehaBhosale_SlidesForEPS2021.pdf

185 Secondary nuclei from O-16 fragmentation at the LHC

Studies of collisions of light systems, like O–O, are planned at the LHC [1]. In particular, the translation of initial collision geometry with alpha-clustering in O-16 to triangular modulation of elliptic flow is discussed [2,3]. To date there were no measurements, even at lower collision energies, which demonstrated such fine effects of radial flow. However, numerous measurements of fragmentation of relativistic O-16 were already performed, see, in particular [4]. Therefore, the clustering of O-16 can be revealed by comparing these data to calculations with and without clustering. In the present work we model the fragmentation of O-16 in collisions with light and heavy nuclei by means of a new version of Abrasion-Ablation Monte Carlo for Colliders (AAMCC) model [5] with accounting for pre-equilibrium clustering of spectator matter. AAMCC model is based on Glauber Monte Carlo model [6] in calculating the numbers of participant and spectator nucleons in colliding nuclei. Because of a half-moon shape of spectator matter, it instantaneously dissociates into several independent hot systems defined by minimum spanning tree (MST) clustering algorithm. It is assumed that the excitation energy of each system correlates with its volume and its decays are simulated by means of Fermi break-up model from the Geant4 toolkit [7]. A small contribution to production of forward fragments from electromagnetic dissociation of O-16 is also calculated with RELDIS model [8]. It is demonstrated that in contrast to Pb–Pb collisions, neutron and proton Zero Degree Calorimeters in the ALICE experiment at the LHC will be less effective in triggering hadronic and electromagnetic interactions of O-16 because of a large number of neutrons and protons remaining in undetected nuclear fragments. As found, the measured production of Li, Be, B and N fragments [4] is described by AAMCC, but the production of carbon is underestimated. At the same time, channels with a single He-4 are overestimated with respect to data [4], but the rates of simultaneous production of two and three He-4 are underestimated. This all indicates that alpha-clustering effects in initial O-16, which give preference to He-4 as fragmentation products of relatively cold spectator matter, have to be taken into account in AAMCC in addition to the considered pre-equilibrium MST clustering.
The work has been carried out with financial support of RFBR within the
project 18-02-40035-mega.

[1] Z. Citron et al., CERN Yellow Rep. Monogr. 7 (2019) 1159
[2] W. Broniowsky et al., Nucl. Phys. A 1005 (2021) 121763
[3] S.H. Lim et al., Phys. Rev. C 99 (2019) 044904
[4] M. El-Nagdy et al., J. Phys. Comm. 2 (2018) 035010
[5] A. Svetlichnyi, I. Pshenichnov, Bull. RAS:Physics 84 (2020) 911
[6] C. Loizides et al., Phys. Rev. C 97 (2018) 054910
[7] J.M. Quesada et al., Prog. Nucl. Sci. Tech. 2 (2011) 936
[8] I.A.Pshenichnov, Phys. Part. Nucl. 42 (2011) 215

Speaker: Aleksandr Svetlichnyi (INR RAS, MIPT(NRU))

Svetlichnyi_EPS_HEP_v1.pdf

T06: QCD and Hadronic Physics: Part 3: PDFs

Note: All contributions are given 12 minutes + 3 min for questions

Convener: laura Fabbietti (TUM)

186 PDF analysis of Z boson polarisation data from LHC and constraints to Higgs boson production cross section by xFitter

Recent developments of the xFitter PDF analysis package and studies based on it are summarised. The emphasis is given to the PDF analysis of the Z boson polarisation data which provide additional constraint to the gluon distribution for Bjorken x below 0.1. Studies using pseudo data samples corresponding to an integrated luminosity of the LHC Run 3 and high-luminosity HL-LHC show that the PDF uncertainty of the Higgs boson production cross section can be reduced significantly.

Speaker: Juri Fiaschi (Westfälische Wilhelms-Universität Münster)

A0xFitter_Fiaschi_EPS_2021.pdf

187 Photon PDF and Impact from heavy flavors in the CT18 global analysis

Building upon the most recent CT18 global fit, we present:
1) A new calculation of the photon content of proton based on an application of the LUXqed formalism.
2) The impact of heavy-flavor production data on the CT18 PDFs family.

CT18 Photon PDF: We explore two principal variations of the LUXqed ansatz. In one approach which we designate CT18lux, the photon PDF is calculated directly using the LUXqed formula for all scales, $Q$. In an alternative realization, CT18qed, we instead initialize the photon PDF in terms of the LUXqed formulation at a lower scale, $Q\approx Q_0$, and evolve to higher scales with a combined QED kernel at ${\cal O}(\alpha)$, ${\cal O}(\alpha \alpha_s)$ and ${\cal O}(\alpha^2)$. Phenomenological implications of these photon PDFs at the LHC are discussed.

Heavy flavors in CT18: We discuss the impact of heavy-flavor production data on the CT18 PDFs family. In particular, we discuss the impact on the CT18 global analysis of the latest charm and bottom production measurements from the H1 and ZEUS collaborations and the differential top-quark pair production cross section measurements from CMS and ATLAS. We discuss tensions and interplays between heavy-quark observables in the global fit and the different pulls on the CT18 gluon.

Speaker: Keping Xie (Pitt Pacc)

EPS2021_combine.pdf

188 NNPDF4.0: The Structure of the Proton at 1% Precision

We present a new release of the NNPDF family of global analyses of the proton's parton distribution functions: NNPDF4.0. It includes a wealth of new experimental data from HERA and the LHC, from dijet cross-sections and isolated photons to single-top and top-quark pair differential distributions. The NNPDF4.0 methodology benefits from improved machine learning algorithms, in particular automated hyperparameter optimisation and stochastic gradient descent for neural network training, which has been validated extensively by means of closure tests and future tests. We demonstrate the stability of the results with respect to the choice of parameterisation basis. We compare NNPDF4.0 with its predecessor NNPDF3.1 as well as to other recent global fits, and study its phenomenological implications for representative collider observables. We assess the impact of representative datasets on specific PDF flavour combinations, such as the dijet and top quark data on the gluon, the Drell-Yan and neutrino DIS data on strangeness, and electroweak measurements on charm and quark flavour separation.

Speaker: Roy Stegeman (University of Milan)

Stegeman_EPSHEP21.pdf

189 Determination of proton parton distribution functions using ATLAS data

We present fits to determine parton distribution functions (PDFs) using inclusive W/Z-boson measurements from the ATLAS experiment at the LHC. The ATLAS measurements are used in combination with deep-inelastic scattering data from HERA. We also present the results of PDF fits that use W/Z+jets measurements from ATLAS in addition to the measurements listed above. An improved determination of the sea-quark densities at high Bjorken, x, is seen, while confirming a strange-quark density similar in size to the up- and down-sea-quark densities in the range x < 0.02 found by previous ATLAS analyses. If available, PDF fits including inclusive W and Z boson production, ttbar production, W+jets and Z+jets production, inclusive jet production and direct photon production will also be presented.

Speaker: Claire Gwenlan (Oxford)

EPS21-Gwenlan-ATLASPDFs.pdf

190 Precision QCD in $ep$ collisions at the LHeC

The LHeC and the FCC-he are the cleanest, high resolution microscopes that the world can build in the nearer future. Through a combination of neutral and charged currents and heavy quark tagging, they will unfold the parton structure of the proton with full flavour decomposition and unprecedented precision. In this talk we will present the most recent studies on the
determination of proton parton densities as contained in 2020 LHeC Conceptual Design Report update [1]. We will also present the results on the determination of the strong coupling constant through the measurement of total and jet cross sections.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e-Print: 2007.14491 [hep-ex], to appear in J. Phys. G.

Speaker: Claire Gwenlan (Oxford)

EPS21-LHeC-PDFs-Gwenlan.pdf

191 Transverse momentum dependent splitting functions in the Parton Branching method

The Parton Branching (PB) approach provides a way to obtain transverse momentum dependent (TMD) parton densities. Its equations are written in terms of splitting functions and Sudakov form factors and can be solved with Monte Carlo methods. Even though the transverse momentum is known in every branching, the PB method currently uses the DGLAP splitting functions, which assume that the parton has no transverse momentum. We propose to extend the PB method by including TMD splitting functions, a concept from high-energy factorization.

We present the evolution equations and the connection to DGLAP evolution equations and BFKL evolution equation. We show their solutions obtained with a Monte Carlo Simulation and show numerically the effects that TMD splitting functions have on the TMD distribution functions.

Speaker: Lissa Keersmaekers (University of Antwerp)

LissaKeersmaekersEPS2021.pdf

192 Jet-based TMD measurements with H1 data

Recently, jet measurements in DIS events close to Born kinematics have been proposed as a new probe to study transverse-momentum-dependent (TMD) PDFs, TMD fragmentation functions, and TMD evolution. We report measurements of lepton-jet momentum imbalance and hadron-in-jet correlations in high-$Q^2$ DIS events collected with the H1 detector at HERA. The jets are reconstructed with the kT algorithm in the laboratory frame. These are two examples of a new type of TMD studies in DIS, which will serve as pathfinder for the Electron-Ion Collider program.

Speaker: Benjamin Nachman (ATLAS (LHC Experiment ATLAS))

EPSHEPH1July2021.pdf

193 Proton 3D imaging via transverse-momentum-dependent gluon densities

In this talk we present exploratory studies of the 3D gluon content of the proton, as a result of analyses on leading-twist transverse-momentum-dependent (TMD) gluon distribution functions, calculated in a spectator model for the parent proton. Our formalism embodies a fit-based parameterization for the spectator-mass density, suited to describe both the small and the moderate-x regime. Particular attention is paid to the $T$-odd gluon TMDs, which represent a key ingredient in the description of relevant spin-asymmetries emerging when the nucleon is polarized, as the gluon Sivers effect. All these analyses are helpful to shed light on the gluon dynamics inside nucleons and nuclei, which is one of the primary goals of new-generation colliders, as the Electron-Ion Collider, the High-Luminosity LHC and NICA-SPD.

Speaker: Francesco Giovanni Celiberto (ECT*/FBK Trento & INFN-TIFPA)

talk_EPS-HEP_2021_Celiberto_gluon_TMDs.pdf

T07: Top and Electroweak Physics: Part 3

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Eleni Vryonidou, Elisabetta Gallo-Voss (CMS (CMS-Experiment))

194 LUXE: A new experiment to study non-perturbative QED in electron-LASER and photon-LASER collisions

The LUXE experiment (LASER Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical LASER and 16.5 GeV electrons from the XFEL electron beam, as well as collisions between the optical LASER and high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where the electromagnetic field of the LASER is above the Schwinger limit. In this regime, QED is non-perturbative. This manifests itself in the creation of physical electron-positron pairs from the QED vacuum, similar to Hawking radiation from black holes. LUXE intends to measure the positron production rate in an unprecedented LASER intensity regime. An overview of the LUXE experimental setup is given, in the context within the field of high-intensity particle physics. The foreseen detector systems and their sensitivity are presented. Finally, the prospects for studying BSM physics are also discussed.

Speaker: Louis Helary (FTX (FTX Fachgruppe SLB))

LUXE_EPS_July2021.pdf

195 Study of $e^+e^-$ annihilation into hadrons at low energies with ISR at BABAR

The measurement of exclusive $e^+e^-$ to hadrons processes is a significant part of the physics program of BABAR experiment, aimed to improve the calculation of the hadronic contribution to the muon $g−2$ and to study the intermediate dynamics of the processes. We present the most recent studies performed on the full data set of about 470 fb$^{−1}$ collected at the PEP-II e+e− collider at a center-of-mass energy of about 10.6 GeV. In particular, we report the results on $e^+e^-$ annihilation into three pions and into states with six and seven pions or kaons, in an energy range from production threshold up to about 4 GeV.

Speaker: Vladimir Druzhinin (BINP, Novosibirsk)

babar-epshep-2021.pdf

196 Vector boson scattering in CMS

Vector boson scattering is a key production process to probe the electroweak symmetry breaking of the standard model, since it involves both self-couplings of vector bosons and coupling with the Higgs boson. If the Higgs mechanism is not the sole source of electroweak symmetry breaking, the scattering amplitude deviates from the standard model prediction at high scattering energy. Moreover, deviations may be detectable even if a new physics scale is higher than the reach of direct searches. Latest measurements of production cross sections of vector boson pairs in association with two jets in proton-proton collisions at sqrt(s) = 13 TeV at the LHC are reported using a data set recorded by the CMS detector. Differential fiducial cross sections as functions of several quantities are also measured.

Speaker: Meng Lu

EPS_2021_VBSinCMS.pdf

197 Recent observation and measurements of vector-boson fusion and scattering with ATLAS

Measurements that exploit the weak vector-boson scattering and weak vector-boson fusion are fundamental tests of the gauge structure of the Standard Model and are sensitive to anomalous weak boson self interactions. In this talk, we present recent results in this contest performed by the ATLAS experiment using proton-proton collisions at sqrt(s)=13 TeV. Measurements of Zjj final states produced via weak-boson fusion are shown, differential cross-section measurements are presented as well as reinterpretation in terms of an effective field theory to constrain new physics beyond the Standard Model. If available, new results on weak-boson production will also be shown.

Speaker: Dag Gillberg

EPS_2021_VBF_VBS.pdf

198 Searches for quartic anomalous coupling at the LHC with intact protons

We will discuss the sensitivity to quartic anomalous couplings between photons and W/Z bosons at the LHC using intact protons in the final state. This allows obtaining a negligible background for 300 fb−1 of data and improves the sensitivities to anomalous couplings by two or three orders of magnitude compared to standard methods. We will also discuss the sensitivity to axion-like particles that also improves by two orders of magnitude.

Speaker: Christophe Royon (The University of Kansas (US))

Royon_eps2021_anomalous.pdf

199 SMEFT analysis of vector boson scattering and diboson data from the LHC Run II

We present a systematic interpretation of vector boson scattering (VBS) and diboson measurements from the LHC in the framework of the dimension-six Standard Model Effective Field Theory (SMEFT), based on our results available at https://arxiv.org/abs/2101.03180.
We try to understand what is the interplay between VBS and diboson measurements in order to constrain 16 independent directions in the dimension-six EFT parameter space, finding that VBS provides complementary information on several operators relevant for the description of the electroweak sector.
Finally we also quantify the ultimate EFT reach of VBS measurements via dedicated projections for the High Luminosity LHC. Our results motivate the integration of VBS processes with Higgs measurements in future global SMEFT interpretations of particle physics data.

Speaker: Giacomo Magni (VU, Nikhef)

Talk22_Magni_EPSHEP21_26_07_21.pdf

200 Measurements of multi-boson production at ATLAS

Measurements of multiple electroweak bosons production at the LHC constitute an important test of the Standard Model. They are sensitive to the properties of electroweak-boson self-interactions and provide a test of the electroweak theory and of the perturbative quantum chromodynamics. In this talk, we present recent results from the ATLAS experiment for multi-boson production in proton-proton collisions at sqrt(s) =13 TeV. The differential cross-section measurement of WW production in association with jets is presented. We also present the measurement of differential cross-sections of four-lepton events, containing two same-flavour, opposite-charge electron or muon pairs.. The data are corrected for detector inefficiency and resolution and are compared to theoretical predictions. The measurements are reinterpreted in terms of an effective field theory to constrain new physics beyond the Standard Model. If available new results on other final states will be also presented

Speaker: Jessica Metcalfe (Argonne National Laboratory)

Metcalfe_EPS-HEP_Multiboson_July26_2021_v8.pdf

201 Multiboson production in CMS

This talk reviews recent measurements of multiboson production using CMS data. Inclusive and differential cross sections are measured using several kinematic observables.

Speaker: Mohammad Wadud (University of Minnesota (US))

EPS_HEP_Multiboson_2021.pdf

T08: Flavour Physics and CP Violation: Part 3

Conveners: Alexander Glazov (BELLE (BELLE II Experiment)), Jorge Martin Camalich (Instituto de Astrofisica de Canarias)

202 New physics searches through $\tau$ decays at Belle

We report the result of a search for $\tau \to \ell \gamma$ ($\ell = e, \mu$) using the full data sample at Belle. Since the observation of neutrino oscillations has unambiguously shown that the lepton flavor is no longer conserved, we can expect lepton flavor violation (LFV) in the charged lepton sector. Though the standard model (SM) does not predict charged LFV decays at an observable rate, $\tau \to \ell \gamma$ is predicted by many new physics scenarios and is thus one of the most promising LFV modes. Consequently, we have obtained the most stringent limit on the branching fraction of $\tau \to \mu \gamma$. In addition, we report the result of a search for tau electric dipole moment (EDM) evaluating $\tau$-$\tau$-$\gamma$ vertex coupling using the full data sample at Belle. At present, the observed CP violation is insufficient to explain the prevalent matter-antimatter asymmetry in our universe. On the other hand, the EDM of leptons is predicted to be negligibly small in the SM and is expected as a source of CPV in the lepton sector induced by some new physics. We have obtained one order more sensitive result both for the real and imaginary parts of the $\tau$ EDM.

Speaker: Sourav Patra (BELLE (BELLE II Experiment))

Sourav_Patra_EPSHEP.pdf

203 Searches for lepton flavour/number violation in K+ and pi0 decays at the NA62 experiment

The NA62 experiment at CERN collected a large sample of charged kaon decays into final states with multiple charged particles in 2016-2018. This sample provides sensitivities to rare decays with branching ratios as low as 10^{-11}. Results from searches for lepton flavour/number violating decays of the charged kaon and the neutral pion to final states containing a lepton pair based on this data set are presented.

Speaker: Elisa Minucci (CERN)

NA62_LNV_LFV_EPS2021.pdf

204 Explaining the Cabibbo Angle Anomaly

The first row of the Cabibbo-Cobayashi-Maskawa (CKM) matrix shows a discrepancy of $\sim 3\sigma$ with unitarity, known as the ”Cabibbo Angle Anomaly” (CAA). After reviewing the origin and status of the anomaly, I investigate the various possibilities to explain it in the context of physics beyond Standard Model (BSM) which can be broadly grouped into three categories: modifications of four-fermion contact operators, modifications of the leptonic W vertices and modifications of the W vertices with quarks. In addition, I also discuss the phenomenological implications in the electroweak (EW) precision observables and low energy observables testing lepton flavour universality (LFU) which have to be taken into account in order to asses the viability of these solutions. Then, I review concrete realizations of BSM physics proposed to solve the CAA, which highlight the correlation with other existing anomalies such as $b\to s\ell\ell$ and $\tau\to \mu\nu\nu$, providing interesting predictions to be tested experimentally in the near future.

Speaker: Claudio Andrea Manzari (University of Zurich)

Explaining_the_Cabibbo_Angle_Anomaly.pdf

205 Tau physics prospects at Belle II

The Belle II experiment is a substantial upgrade of the Belle detector and will operate
at the SuperKEKB energy-asymmetric e+e− collider. The design luminosity of the machine
is 8 × 1035 cm−2s−1 and the Belle II experiment aims to record 50 ab−1 of data, a factor
of 50 more than its predecessor. From February to July 2018, the machine has completed a
commissioning run and main operation of SuperKEKB has started in March2019. Belle II has
a broad τ physics program, in particular in searches for lepton flavour and lepton number
violations (LFV and LNV), benefiting from the large cross section of the pair wise τ
lepton production in e+e− collisions. We expect that after 5 years of data taking, Belle II
will be able to reduce the upper limits on LF and LN violating τ decays by an order of
magnitude. Any experimental observation of LFV or LNV in τ decays constitutes an unambiguous
sign of physics beyond the Standard Model, offering the opportunity to probe the underlying
New Physics. In this talk we will review the τ lepton physics program of Belle II.

Speaker: Alejandro De Yta Hernandez (BELLE (BELLE II Experiment))

EPS_tauBelleII_adeyta.pdf

206 Latest dark sector searches at the Belle Experiment

The Belle experiment has accumulated close to $1\,{\rm ab}^{-1}$ of data in electron-positron collisions at center-of-mass energies around various $\Upsilon(nS)$ resonances. These data can be used to perform a number of new physics searches in the context of dark sector with an unprecedented precision. We present for the first time the results of a search of the dark photon in $B$-meson decays, the search for dark matter in bottomonium decays, as well as the latest results in the search for dark forces, via direct production, or in the decay of mesons. These competitive results can be used to severely constrain new physics scenarios.

Speaker: Seokhee Park (BELLE (BELLE II Experiment))

EPS-HEP-210726-psh.pdf

207 Flavor physics at FCC-ee with focus on Bc->tau nu

Z-pole operation at FCC-ee offers a unique laboratory for flavor physics, with the anticipated production of 10^12 b-quarks and the opportunity for triggerless data-taking in a clean e+e- collision environment. Using new simulation and analysis tools developed for FCC-ee physics and performance studies, theoretically compelling beauty, charm, and tau decay modes are studied in order to evaluate key performance metrics and expected yields. Comparisons with LHCb Upgrade and Belle-II are performed, in order to highlight areas within flavor physics where FCC-ee measurements can be highly impactful.

Speaker: Clement Helsens (CERN)

Helsens_FlavourPhysics_FCCee_EPS2021.pdf

208 Measurement of the neutron electric dipole moment in the nEDM and n2EDM experiments

The electric dipole moment (EDM) of the neutron is a strong probe of CP violation beyond the Standard Model.
In particular, its value could reveal information on baryogenesis.
We report the latest result from the nEDM collaboration, which operates an experiment to measure the neutron EDM at the Paul Scherrer Institute
using Ramsey’s method of separated oscillating magnetic fields with ultracold neutrons.
The estimation of systematic effects profited from an unprecedented knowledge of the magnetic field relying on the use of both a 199Hg comagnetometer and an array of optically pumped cesium vapor magnetometers
The total uncertainty is dominated by the statistics and the observe EDM is compatible with zero. A new improved limit, |d|<1.8e-26 e.cm @ 90% CL, was computed.
The systematic precision was improved by a factor 5 with respect to previous experiments opening the way to improved sensitivity in the next generation experiment, n2EDM
which is being build at PSI for an operation starting 2022.

Speaker: Benoit Clément (LPSC - Université Grenoble Alpes)

EPS2021_NEDM_CLEMENT .pdf

209 Study of hadronic $B$ and $B_s$ decays at Belle

We report the first search for the penguin-dominated process $B_{s} \to \eta^{\prime} X_{s\bar{s}}$ using a semi-inclusive method. In absence of a statistically significant signal, we set a 90\% confidence-level upper limit $1.4 \times 10^{-3}$ on the partial branching fraction where $M(X_{s\bar{s}}) \leq 2.4\,{\rm GeV}$. We also report final results for the $B^{0}_{s} \to D_{s} X$ and $B^{0}_{s} \to \eta \eta^{\prime}$ decays. These results are obtained using $121.4\,{\rm fb}^{-1}$ data collected at the $\Upsilon(5S)$ resonance by the Belle experiment at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. Furthermore, we report on measurements involving three-body decays $B^{+} \to K^{+} K^{-} \pi^{+}$ and $B^{+} \to \pi^{+} \pi^{0} \pi^{0}$ based on the Belle data collected at the $\Upsilon(4S)$ resonance.

Speaker: Shawn Dubey

eps_hep_2021_sdubey_parallel.pdf

T09: Higgs Physics: Yukawa - part 2

Conveners: meng xiao (zhejiang university), Sarah Heim (DESY), Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris), Michael Trott (NBI)

210 Hbb dead or alive?

Hbb associated production is often advocated as an ideal proxy to measure the bottom-quark Yukawa coupling yb. However, large irreducible background exists, which make the extraction of yb very challenging, if not impossible. I will discuss some recent calculations which showed how gluon-fusion, VH and VBF production conspire to kill our sensitivity on yb from Hbb at the LHC.

Speaker: Marco Zaro (University and INFN Milano)

zaro-hbb-eps-jul21.pdf

211 Measurements of Higgs boson production in decays to two tau leptons with the ATLAS detector

Testing the couplings of the Higgs boson to leptons is important to understand the origin of lepton masses. This talk presents measurements of Higgs boson production in Higgs boson decays to two tau leptons based on pp collision data collected at 13 TeV.

Speaker: Michaela Mlynarikova (Northern Illinois University)

EPS2021_Htauatu_approved.pdf

212 Measurements of Higgs boson cross sections and differential distributions in leptonic final states (CMS)

The latest results obtained with CMS data collected at a centre-of-mass energy of 13 TeV targeting Higgs boson decays in leptonic final states at CMS will be discussed.

Speaker: Andrew Loeliger (University Of Wisconsin Madison)

EPS_HiggsToLeptons_v5.pdf

213 Search for rare decays of the Higgs boson with the ATLAS detector

The Standard Model predicts several rare Higgs boson decay channels, among which are decays to a Z boson and a photon, H→Zγ, and to a low-mass lepton pair and a photon H→ℓℓγ. The observation of these decays could open the possibility of studying the CP and coupling properties of the Higgs boson in a complementary way to other analyses. Results based on 139 fb−1 of pp collision data collected at 13 TeV will be presented.

Speaker: Artem Basalaev (ATLAS (ATLAS Dark Matter with Higgs))

Basalaev_Rare_Higgs_EPS2021.pdf

214 Measurements of Higgs boson properties and couplings at CMS

Recent measurements of Higgs boson properties and couplings will be presented.

Speaker: Dr Ulascan Sarica (UCSB)

20210726.pdf

215 Searches for rare Higgs boson decays (CMS)

Recent measurements of rare SM Higgs boson decays will be presented.

Speaker: Silvio Donato (INFN Pisa)

HiggsRare_Donato.pdf

216 Searches for Higgs invisible (CMS)

Recent CMS searches for Higgs Invisible decays will be presented.

Speaker: Vukasin Milosevic (IHEP Beijing)

EPS2021_VM_CINCO_v3.pdf

T10: Searches for New Physics: Part 3

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Pedro Schwaller (Johannes Gutenberg University Mainz)

217 Possible indications for new Higgs bosons in the reach of the LHC: N2HDM and NMSSM interpretations

In several searches for additional Higgs bosons at the LHC, in particular the CMS search in the $pp \to \phi \to t \bar t$ channel and the ATLAS search in the $pp \to \phi \to \tau^+\tau^-$ channel, a local excess at the level of $3\,\sigma$ or above has been observed at a mass scale of $m_\phi \approx 400$~GeV. We investigate to what extent a possible signal in those channels could be accommodated in the Next-to-Two-Higgs-Doublet Model (N2HDM) or the Next-to Minimal Supersymmetric Standard Model (NMSSM). In a second step we furthermore analyse whether such a model could be compatible with both a signal at $\approx 400$~GeV and at $\approx 96$~GeV, where the latter possibility is motivated by observed excesses in searches for the $b \bar b$ final state at LEP and the di-photon final state at CMS. The analysis for the N2HDM reveals that the observed excesses at $\approx 400$~GeV in the observed excesses at $\approx 400$~GeV in the $pp \to \phi \to t \bar t$ and $pp \to \phi \to \tau^+\tau^-$ channels point towards different regions of the parameter space, while one such excess and an additional Higgs boson at $\approx 96$~GeV could simultaneously be accommodated. In the context of the NMSSM an experimental confirmation of a signal in the $t \bar t$ final state would favor the alignment-without-decoupling limit of the model, where the Higgs boson at $\approx 125$~GeV could be essentially indistinguishable from the Higgs boson of the SM. In contrast, a signal in the $\tau^+\tau^-$ channel would be correlated with significant deviations of the properties of the Higgs boson at $\approx 125$~GeV from the ones of a SM Higgs boson that could be detected with high-precision coupling measurements.

Speaker: Thomas Biekoetter (T (Phenomenology))

slides_biekotter.pdf

218 A 96 GeV Higgs Boson in the 2HDMS

We discuss a ∼ 3 σ signal (local) in the light Higgs-boson search in the diphoton decay
mode at ∼ 96 GeV as reported by CMS, together with a ∼ 2 σ excess (local) in the bb̄
final state at LEP in the same mass range. We interpret this possible signal as a Higgs
boson in the 2 Higgs Doublet Model with an additional complex Higgs singlet (2HDMS).
We find that the lightest CP-even Higgs boson of the 2HDMS type II can perfectly
fit both excesses simultaneously, while the second lightest state is in full agreement
with the Higgs-boson measurements at 125 GeV, and the full Higgs-boson sector is
in agreement with all Higgs exclusion bounds from LEP, the Tevatron and the LHC
as well as other theoretical and experimental constraints. We derive bounds on the
2HDMS Higgs sector from a fit to both excesses and describe how this signal can be
further analyzed at the LHC and at future e⁺e⁻ colliders, such as the ILC. We analyze
in detail the anticipated precision of the coupling measurements of the 96 GeV Higgs
boson at the ILC.

Speaker: Steven Paasch (FLC (FTX Fachgruppe SLB))

thdms.pdf

219 Searches and techniques for boosted resonances (non-diboson) with the ATLAS detector

Many new-physics signatures at the LHC produce highly boosted particles, leading to close-by objects in the detector and necessitating jet substructure techniques to disentangle the hadronic decay products. This talk presents the latest ATLAS results for searches for heavy W’ and Z’ resonances in top-bottom, di-top and 4-top final states using 13 TeV data. It will explain the techniques used, including new top-tagging techniques using machine learning and the use of large-radius jets containing electrons.

Speaker: Chris Malena Delitzsch (University of Arizona)

EPS_ATLAS_boosted_techniques_EXOT.pdf

220 Heavy $Z^\prime$ Bosons in the Secluded $U(1)^\prime$ Model at Hadron Colliders

We study $Z^{\prime}$ phenomenology at hadron colliders in an $U(1)^{\prime}$ extended MSSM. We choose a $U(1)^{\prime}$ model with a secluded sector, where the tension between the electroweak scale and developing a large enough mass for $Z^{\prime}$ is resolved by incorporating three additional singlet fields into the model. We perform a detailed analysis of the production, followed by decays, including into supersymmetric particles, of a $Z^{\prime}$ boson with particular emphasis on its possible discovery. We select three different scenarios consistent with the latest available experimental data and relic density constraints, and concentrate on final signals involving $2\ell+\not\!\!E_{T}$,$4\ell+\not\!\!E_{T}$ and $6\ell+\not\!\!E_{T}$. Including the SM background from processes with two, three or four vector bosons, we show the likelihood of observing a $Z^\prime$ boson is not promising for the HL-LHC at 14 TeV, but optimistic for 27 and 100 TeV.

Speaker: Levent Selbuz (Ankara University)

EPS-HEP2021_selbuz.pdf

221 Search for heavy BSM particles coupling to third generation quarks at CMS

We present results from searches for resonances with enhanced couplings to third generation quarks, based on proton-proton collision data at a centre-of-mass energy of 13 TeV recorded by CMS. The signatures include single and pair production of vector-like quarks and heavy resonances decaying to third generation quarks. A wide range of final states, from multi-leptonic to entirely hadronic is covered. Jet substructure techniques are employed to identify highly-boosted heavy SM particles in their hadronic decay modes.

Speaker: Anna Benecke (UCLouvain)

20210726_B2G_Benecke.pdf

222 Searches for vector-like quarks with the ATLAS Detector

Vector like quarks appear in many theories beyond the Standard Model as a way to cancel the mass divergence for the Higgs boson. The talk will focus on the most recent results using 13 TeV pp collision data collected by the ATLAS detector. This presentation will address the analysis techniques, in particular the selection criteria, the background modeling and the related experimental uncertainties. The results and the complementarity of the various searches, along with the phenomenological implications, will be discussed.

Speaker: Mesut Unal (Austin)

EPS-HEP2021_MUNAL_VLQ_ATLAS.pdf

223 Searches for leptoquarks with the ATLAS detector

Leptoquarks (LQ) are predicted by many new physics theories to describe the similarities between the lepton and quark sectors of the Standard Model and offer an attractive potential explanation for the lepton flavour anomalies observed at LHCb and flavour factories. The ATLAS experiment has a broad program of direct searches for leptoquarks, coupling to the first-, second- or third-generation particles. This talk will present the most recent 13 TeV results on t he searches for leptoquarks and contact interactions with the ATLAS detector, covering flavour-diagonal and cross-generational final states.

Speaker: Yoav Afik (CERN)

ATLAS_LQ_Searches.pdf

224 Precise LHC limits on the U_1 leptoquark parameter space

The $U_1$ leptoquark is the popular candidate to explain the persistent 𝐵-anomalies. In this talk, I will discuss the bounds which can be imposed on a $U_1$ leptoquark model using the latest LHC data. The current LHC data is quite sensitive towards the mass of $U_1$ and its couplings with the Standard Model second and third-generation fermions. I will discuss some simple scenarios with different couplings that can contribute to the relevant operators and show that the LHC data either rule out or severely constrain these simple $U_1$ scenarios. I will discuss how a TeV range $U_1$ can survive the LHC limits (from both dilepton and direct search data) and explain the anomalies. I will also point out some search channels for $U_1$.

Speaker: Arvind Bhaskar (International Institute of information technology)

arvind_EPS_HEP_2021.pdf

T12: Detector R&D and Data Handling: Instrumentation 1

Conveners: Vincent Boudry (LLR – École polytechnique), Dr Alessandro Cardini (INFN Sezione di Cagliari, Italy)

225 Cryogenic SiPMs for dark matter search with DarkSide-20k

The Global Argon Dark Matter Collaboration is pursuing the construction, at the Gran Sasso Laboratory (LNGS), of DarkSide-20k a dark matter direct search experiment designed as a 20-tonne fiducial mass Time Projection Chamber (TPC) with SiPM based photosensors, expected to be free of any instrumental background for an exposure of >100 ton x years.
Large-area cryogenic SiPM tile modules (PDM) have been developed with lower
radiogenic background and higher photo-detection efficiency (>40%) respect to the PMTs usually adopted in dark matter experiments. Two units made of $25 \times 25$ cm$^2$ arrays of PDMs have been operated and characterized at liquid nitrogen and argon temperatures in small prototype detectors. Several options are currently pursued for transmission of the analog signals to the digitisation electronics at room temperature.
More than 8280 PDMs are needed to fully instrument the DarkSide-20k Liquid Argon TPC. The
assembly will take place in NOA, a 700 m$^2$ clean room under construction at
LNGS that will host a dedicated microelectronics packaging facility. The
present status of DarkSide-20k with the latest achievements and the future
steps and strategies will be presented.

Speaker: Iza Kochanek

Kochanek-eps-2021.pdf

226 New radiation-hard scintillators for FCC detectors

Future circular and linear colliders as well as the Large Hadron Collider in the High-Luminosity era have been imposing unprecedented challenges on the radiation hardness of particle detectors that will be used for specific purposes e.g. forward calorimeters, beam and luminosity monitors.
We performed research on the radiation-hard active media for such detectors, particularly calorimeters, by exploring intrinsically radiation-hard materials and their mixtures.The initial samples that we probed were thin plates of Polyethylene Naphthalate (PEN) and Polyethylene Terephthalate (PET) and thin sheets of HEM. The previous studies indicate towards promising performance under high radiation conditions. We will report on the necessary process of mixing the PEN and PEN for optimized scintillation and signal timing properties preserving the high radiation resistance.
Recently we developed a new plastic scintillator material. The scintillation yield of SX sample was compared to a BGO crystal using a setup with 90Sr source and a Hamamatsu R7525-HA photomutiplier tube (PMT). The SX was measured to yield roughly 50% better light production compared to the BGO crystal.sample SX was irradiated at the CERN PS radiation facility with 24 GeV/c protons. The samples received a fluence of 1.2 x 1015 p/cm2 which corresponds to 4 x 105 Gy radiation doses. The comparison of the transmission spectra of SX sample before and after the irradiation exhibits a loss of roughly 7% light transmission after 4 x 105 Gy proton irradiation

Speaker: Prof. Yasar Onel (University of Iowa (US))

EPSHEP_Bilki_Onel.pdf

227 Fast neutron detection with GAGG/SiPM matrix detector

The spectacular progress in the improvement of scintillation properties of Ce doped Gd-based crystalline compounds was demonstrated in the last decade. That makes possible use of these materials for neutron detection, similarly to Li-based inorganic scintillators. Particularly, the materials of interest are compositionally disordered Gd3Al2Ga3O12 (GAGG) garnets, which are tolerant to a different kind of ionizing radiation, exhibit a high light yield of up to ~50000 photons/MeV, have scintillation decay time shorter than 80 ns, time resolution of annihilation -quanta ~160ps. Their emission band peaks at ~520 nm matching the sensitivity spectrum of the silicon photomultipliers (SiPMs). Recently we demonstrated the response of GAGG based detector to neutrons of Am(Pu)-Be sources [1,2]. Natural gadolinium is a mixture of six stable isotopes, two of which, 155Gd and 157Gd, have a high cross-section of the thermal neutron capture, 61000 and 254000 barns, respectively. Moreover, Gd nuclei possess a set of resonances providing resonance integral ~400 bn. The capture of the neutrons is accompanied by the emission of γ-quanta of different energy, which can be detected in the same scintillation material. The role of the neutron capture by Gd is diminished when their energy reaches a few MeV, and an interaction with 69Ga,71Ga via new channels ((n,p) and (n,α) becomes dominating. Here we report on results of the measurement of neutrons obtained at the bombardment of the Pb 5 cm thick target with a 200 MeV proton beam. The capabilities of the Time-Off-Flight measurement at the short base 0.5m and Pulse Shape Discrimination of the different secondaries were demonstrated. Our results prove the GAGG-based detectors are promising to construct short-flight-base neutron spectrometers utilizing the PSD signals analysis.
1. M Korjik, KT Brinkmann, G Dosovitskiy, V Dormenev, A Fedorov, D Kozlov, Compact and Effective Detector of the Fast Neutrons on a Base of Ce-doped Gd3Al2Ga3O12 Scintillation Crystal., IEEE Transactions on Nuclear Science 66 (1)(2019), 536-540, 7
2. 2. A Fedorov, V Gurinovich, V Guzov, G Dosovitskiy, M Korzhik, V Kozhemyakin, A Lopatik, D Kozlov, V Mechinsky, V Retivov, Sensitivity of GAGG based scintillation neutron detector with SiPM readout, Nuclear Engineering and Technology 52(2020) 2306-2312

Speaker: Prof. Mikhail Korzhik (NRC Kurchatov Institute)

Korzhik-26-07-21-fin.pdf

228 Performance of high-granularity resistive Micromegas at high particle rates and future developments

We present the latest performance studies of high-granularity resistive Micromegas detectors for tracking applications in high-rate environment.
With the aim of developing resistive Micromegas able to efficiently and reliably work in HEP experiments where particle fluxes as high as 10 MHz/cm$^2$ are expected, we have built and characterised several prototypes with high-granularity readout plane, with 3 mm$^2$ size pads, and different resistive protection schemas exploiting a pad-patterned layer or two uniform DLC layers.
We will present the latest results on the detector performance at high rate obtained with tests in laboratory and with particle beams, with a detailed comparison of the resistive schemas and assessment of their potential.
The next step of the project is to make the routing of the readout channels simpler, allowing the construction of larger detectors while keeping the construction process affordable. We are addressing this challenge by the integration of the readout electronics on the back side of the Micromegas board, which leads to a highly integrated device. Preliminary results obtained with the first prototype with embedded APV chip will be presented.

Speaker: Paolo Iengo (INFN)

Iengo-RHUM-EPS2021.pdf

229 ReD: characterisation of a SiPM based Liquid Argon TPC for directional dark matter detection studies

A double-phase argon Time Projection Chamber (TPC), with an active volume of $5\times 5 \times 5$ cm$^3$, has been designed and constructed for the Recoil Directionality (ReD) experiment, within the DarkSide collaboration. The aim of the ReD project is to investigate the directional sensitivity of argon-based TPCs via columnar recombination to nuclear recoils in the energy range of interest (20-200\,keV$_{nr}$) for direct dark matter searches. The key novel feature of the ReD TPC is a readout system based on cryogenic Silicon Photomultipliers (SiPMs), which are employed and operated continuously for the first time in an argon TPC. Over the course of six months, the ReD TPC had been characterised under various operating conditions using $\gamma$-ray and neutron sources, demonstrating stability of the optical sensors and reproducibility of the results.
The scintillation gain and ionisation amplification of the TPC were measured to be $g_1 = (0.194 \pm 0.013)$ photoelectrons/photon and $g_2 = (20.0 \pm 0.9)$ photoelectrons/electron, respectively. The ratio of the ionisation to scintillation signals (S2/S1), instrumental for the positive identification of a candidate directional signal induced by WIMPs, has been investigated for both nuclear and electron recoils. At a drift field of 183 V/cm, an S2/S1 dispersion of 12% was measured for nuclear recoils of approximately 60-90 keV$_{nr}$, as compared to 18% for electron recoils depositing 60\,keV of energy. The detector performance discussed in this talk will allow the investigation of a directional effect due to columnar recombination. In addition a phenomenological parameterisation of the recombination probability in liquid argon is presented and employed for modeling the dependence of scintillation quenching and charge yield on the drift field for electron recoils between 50-500 keV and fields up to 1000 V/cm.

Speaker: Yury Suvorov (UNINA / INFN Sez. Napoli)

EPS_2021_RED_Yury_Suvorov.pdf

230 An Alternative Design for Large Scale Liquid Scintillator Detectors

Single page abstract attached as a pdf.

Speaker: Iwan Morton-Blake (University of Oxford)

EPS_SLIPs_IwanMorton-Blake.pdf

231 The Water Cherenkov Test Experiment at CERN

Water Cherenkov detectors play a crucial role in the study of neutrinos, providing an affordable way to instrument enormous target masses. As neutrino experiments transition from discovery to precision measurement understanding the performance of these detectors becomes more and more important – in the latest T2K oscillation result the Super-Kamiokande detector uncertainty is the largest systematic error on the oscillated event samples. For the next generation experiments Hyper-Kamiokande, ESSnuSB and THEIA, a comprehensive understanding of the detector will be essential.

The Water Cherenkov Test Experiment (WCTE) is a proposed experiment at CERN that will study the response of water Cherenkov detectors to hadron, electron, and muon beams. The aim of the experiment is to test new photosensor technologies such as multi-PMT modules and apply calibration techniques with known particle fluxes to demonstrate a $1\%$ level calibration for GeV scale neutrino interactions. WCTE will also measure Cherenkov light production, pion scattering and secondary neutron production to provide direct inputs to the currently operating T2K and Super-K experiments. This talk describes the WCTE physics program, the detector design and its proposed implementation at the CERN T9 test beam area.

Speaker: Mark Scott (Imperial College London)

MScott_WCTE_EPS2021.pdf

232 Plastic scintillator production involving Additive Manufacturing

Plastic scintillator detectors are widely used in high-energy physics. Often they are used as active neutrino target, both in long and short baseline neutrino oscillation experiments. They can provide 3D tracking with 4$\pi$ coverage and calorimetry of the neutrino interaction final state combined with a very good particle identification, sub-nanosecond time resolution. Moreover, the large hydrogen content makes plastic scintillator detectors ideal for detecting neutrons.
However, new experimental challenges and the need for enhanced performance require the construction of detector geometries that are complicated using the current production techniques. The solution can be given by additive manufacturing, able to quickly make plastic-based objects of any shape.
The applicability of 3D-printing techniques to the manufacture of polystyrene-based scintillator will be discussed. We will report on the feasibility of 3D printing polystyrene-based scintillator with light output performances comparable with the one of standard production techniques. The latest advances on the R\&D aim at combining the 3D printing of plastic scintillator with other materials such as optical reflector or absorber. The status of the R\&D and the latest results will be presented.

Speaker: Davide Sgalaberna (ETH Zurich)

3DSCINT - EPS-HEP 2021.pdf

Tuesday, 27 July

T01: Astroparticle and Gravitational Waves: Part 4

233 Galactic cosmic-ray propagation

I will give an overview of the relevant physics and the challenges of Galactic cosmic-ray transport. In particular, I will address recent developments in numerical modelling and physical developments on this field. Corresponding numerical models aim at reproducing cosmic-ray spectra and also diffuse gamma-ray emission from the Galaxy from high to very-high energies. For these numerical models we witness a transition from analytically prescribed two-dimensional azimuthally-symmetric models to those that use a more realistic description for our Galaxy. Focusing on results computed with the cosmic-ray propagation code PICARD, I will address the new aspects that can be incorporated in such three-dimensional models. This includes, e.g., the impact of observation-driven cosmic-ray source distributions and also the possibility to investigate the effect of anisotropic diffusion with respect to the local magnetic field.

Speaker: Ralf Kissmann (Universität Innsbruck)

Talk_RK_EPS-HEP2021.pdf

234 Propagation of extragalactic cosmic rays in the Galactic magnetic field

The propagation of extragalactic cosmic rays (EGCRs) in the Galactic magnetic field (GMF) plays a crucial role in understanding the CR signal measured at Earth. Particularly in understanding the transition region from Galactic cosmic rays (GCRs) to EGCRs ($ \approx 10^{15.5} \, {\rm eV} – 10^{18.5} \, {\rm eV}$), the GMF is expected to exhibit a range of effects on CRs as this energy range also constitutes a change in propagation regimes from diffusive to ballistic, which are central to understanding the exact nature of this transition.
Using simulation studies with CRPropa3, we study the propagation effects that the GMF have on CRs in the rigidity range $10^{16} \, {\rm V} – 10^{20} \, {\rm V}$ for both isotropically and anisotropically injected EGCRs. As a result, we find that the GMF neither modifies the flux nor the arrival direction distribution in case of isotropic injection across the entire rigidity range. For injection of dipole-like flux anisotropies as well as for single point sources, we find that the arrival direction distribution is consistent with isotropy below rigidites of $10^{18} \, {\rm V}$, and the remaining anisotropy for all particles integrated above rigidities of $10^{18} \, {\rm V}$ manifests in the form of dipoles at the $1–10 \%$-level. Flux modification across the entire rigidity range occur dependent on the direction and nature of the anisotropy. We discuss the consequences of these findings to interpretations of observational results in the transition region from GCRs to EGCRs.

Speaker: Alex Kääpä (Bergische Universität Wuppertal)

presentationKaeaepaeEPSHEP.pdf

235 Mass composition modelling at sources of ultra-high energy cosmic rays

Extragalactic sources are thought to be the origin of the highest energy cosmic rays detected at Earth. In this work, we explore energy-dependent mass compositions of these sources taking a subset of the VCV catalog for distances shorter than z=0.6. We use a power-law spectrum with an exponential cutoff to model individual sources above 10$^{18}$ eV. To be more realistic we use the individual distance and flux weight of the sources, while sharing other properties as the index, Z-dependent rigidity cut and nuclei fraction. We propagate the different nuclei using CRPropa and search for the best stable parameters that fit the features of the spectrum measured by the Pierre Auger Observatory. We show the mass composition at the sources for A = 1, 1 < A ≤ 4, 4 < A ≤ 22, 22 < A ≤ 38 and A > 38.

Speaker: Jose Bazo (Pontificia Universidad Católica del Perú)

EPSHEP_658_JBazo.pdf

236 Implications of turbulence dependent diffusion on cosmic ray spectra

The propagtion of cosmic rays can be described by diffusive motion in most galactic enviroments. Therfore, a detailed knowlege of the diffusion tensor is necessary. Recent analyses of the energy dependence of the diffusion tensor show a function of the turbulence level $b/B$, i.e. $\kappa_i \propto E^{\gamma_i}$ with $\gamma_i = \gamma_i(b/B)$, where $i\in \{\parallel, \perp\}$. (Reichherzer et al, MNRAS 498:5051–5064 (2020))

In this talk we show the implication of this turbulence-dependent diffusion on the radial dependence of the cosmic-ray spectral index and the transition between parallel and perpendicular component. Finally, we interpret the cosmic-ray gradient detected by Fermi in the light of these findings.

Speaker: Julien Dörner (Ruhr University Bochum, RAPP-Center)

turbulence-dependent-diffusion.pdf

10:35 Coffee Break

237 The KM3NeT neutrino telescopes: status and perspectives

The KM3NeT international collaboration has started to build two underwater neutrino telescopes, located in two deep sites of the Mediterranean Sea. ARCA (Astroparticle Research with Cosmics in the Abyss) in its final configuration will instrument 1 Gton of seawater, using more than 100,000 PMTs with a 3” diameter. ARCA is optimised to detect cosmic neutrinos within an energy range of 1 TeV – 10 PeV; it will provide an excellent view of the Southern Sky, including the Galactic Centre. ORCA (Oscillation Research with Cosmics in the Abyss) will be a smaller detector, with an instrumented volume of few Mtons. The photosensors are distributed in a more compact lattice for ORCA, in order to reveal atmospheric neutrinos in the 1 – 100 GeV range.

ORCA is running in a 6-line configuration since more than one year. ARCA has recently completed the installation of new strings, bringing the total number of active lines to 6. The 12 DUs of ARCA and ORCA represent the first core towards full construction of KM3NeT, with new deployment campaigns foreseen in the next months and years at the two installation sites.

This talk will focus on the status and the long-term perspectives for the detector completion, together with a description of the main technological solutions adopted. The ARCA and ORCA science program for neutrino astronomy will be presented. Finally, a preliminary analysis of the ARCA 6-line data will be discussed.

Speaker: Simone Biagi (INFN-LNS)

KM3NeT-Biagi.pdf

238 Searching for High-Energy Neutrinos from Ultra-Luminous Infrared Galaxies with IceCube

Ultra-luminous infrared galaxies (ULIRGs) have total infrared luminosities that exceed $10^{12}$ solar luminosities, making them the most luminous objects in the infrared sky. They are mainly powered by starbursts with star-formation rates exceeding 100 solar masses per year, with a possible secondary contribution from an active galactic nucleus (AGN). Both starburst regions and AGN are environments in which hadronic acceleration, and hence neutrino production, is plausible. In this work we present the results of a stacking search for high-energy neutrinos from a representative sample of 75 local ULIRGs using 7.5 years of IceCube data. No significant neutrino excess is found. We therefore report upper limits on the neutrino flux originating from these 75 ULIRGs, and extrapolate these to limits on the full ULIRG source population. We also compare these results with model predictions.

Speaker: Pablo Correa

EPS-HEP2021_ULIRG_stacking_IceCube_PabloCorrea.pdf

239 The ANTARES neutrino telescope (on behalf of the ANTARES Collaboration)

Installed at about 2500 m under the Mediterranean Sea, in front of the southern French coast, the ANTARES detector is the first undersea neutrino telescope and has been collecting data since 13 years in its final configuration. Its main scientific goal is the search for astrophysical high energy neutrinos, either coming from resolved sources, or as a diffuse excess of very high energy events, or in space-time coincidence with other cosmic messengers such as gravitational waves and electromagnetic signals over the whole energy spectrum.
The good optical properties of sea water yield the reconstruction of neutrino directions with a resolution better than one degree, allowing for all-flavour astronomy. The location of ANTARES, in the Northern hemisphere, also offers a privileged point of view towards the Galactic plane and centre, where interesting high energy candidate sources could be hosted.
In this contribution a general view of the most important scientific achievements of ANTARES will be given, with particular focus on its wide program of multi-messenger research.

Speaker: Annarita Margiotta (Alma Mater Studiorum Università di Bologna and INFN - Bologna)

Talk_EPS-HEP21_Antares__AMargiotta.pdf

T03: Dark Matter: Part 4

Convener: M. Patrick Decowski (Nikhef and the University of Amsterdam)

240 Dark Matter bound states inside the early Universe plasma

WIMPs at the TeV mass region or above experience long-range force effects, such as the existence of meta-stable bound state pairs (WIMPonium). These bound states contribute to the depletion of the relic abundance and therefore allow for even larger WIMP masses to compensate for the effect. In this talk, I present new next-to-leading order (NLO) zero and finite temperature corrections for unbroken non-Abelian electric dipole transitions between any singlet and adjoint two-particle states. After having proven the gauge invariance, infrared and collinear safety of the derived cross sections from thermal field theory, it is demonstrated that the early Universe plasma environment, which enters at NLO, leads to an enhancement of all rates in the full chemical network of existing bound states. Surprisingly, inside the plasma the hierarchy of rates is generically inverted. I.e. capture into the ground state for example can be the slowest process at relevant times, which is in clear contrast to expectations from the mostly considered LO computation. This gives us a novel understanding of the description of such systems. I also present some implications on the relic abundance.

Speaker: Tobias Binder (Kavli IPMU)

TBinder.pdf

241 String Fragmentation in Supercooled Confinement and implications for Dark Matter

A strongly-coupled sector can feature a supercooled confinement transition in the early universe. When fundamental quanta of the strong sector are swept into expanding bubbles of the confined phase, the distance between them is large compared to the confinement scale. The flux linking the fundamental quanta then deforms and stretches towards the wall, producing an enhanced number of composite states upon string fragmentation. The composite states are highly boosted in the plasma frame, which leads to additional particle production through the subsequent deep inelastic scattering. I will discuss the modelling of these dynamics and introduce the consequences for the abundance and energetics of particles in the universe and for bubble-wall Lorentz factors. As a case of study, I will show that the composite dark matter relic density is affected by many orders of magnitude.

Speaker: Yann Gouttenoire (not set)

242 Status of the LUX-Zeplin Detector

The nature and origin of dark matter are among the most compelling mysteries of contemporary science. For over three decades, physicists have been trying to detect dark matter particles via collisions on target nuclei. Noble gases, in particular Xenon, have demonstrated leading sensitivities to WIMP-type dark matter due to their excellent radiopurity, chemical inertness, self-shielding, and particle discrimination properties. LUX-ZEPLIN (LZ) is located 1.5 km underground at the Sanford Underground Research Facility in Lead, South Dakota. By utilizing 7 tonnes of active liquid Xenon, the world’s largest target mass, in a dual-phase time-projection chamber LZ will achieve a sensitivity of 1.4x10^(−48) cm^2 to 40 GeV WIMPs in a 1000 day exposure. To achieve the backgrounds necessary for this experiment a rigorous radioassay, radon emanation, and cleanliness programs were employed and an active veto detector is built around the TPC. This presentation gives an overview of the LZ experiment, its design goals, and the status of construction and operations.

Speaker: Björn Penning (University of Michigan)

LZ_Status_EPS_2021_Penning.pdf

243 The XENON Dark Matter Project

Understanding the nature of the Dark Matter is one of the biggest challenges in frontier science today. Astrophysical and cosmological observations provide strong evidence for its existence. Several proposed candidates have been put forward over time: one of the most compelling are Weakly Interacting Massive Particles (WIMPs). The XENONnT dark matter program aims at finding direct evidence for the scattering of WIMPs with xenon target nuclei in an ultra-low background dual-phase time projection chamber detector located in the underground National Laboratory of Gran Sasso in Italy.
XENON1T currently achieves the most stringent limits on WIMP (Weakly Interacting Massive Particle) parameters. The technology is evolving rapidly since the last decade and, XENONnT is expected to continue
leading the field.
I will review the current status of the XENON program and the recent Dark Matter results from the XENON1T experiment. The scientific reach of the XENON1T/XENONnT experiments will be completed with the future generation (the DARWIN project) aiming at 40 tons of liquid xenon.

Speaker: Julien Masbou

2021_07_27_EPS_HEP_2021_XENON.pdf

244 Status of the DEAP-3600 Dark Matter Search at SNOLAB

The latest results from DEAP-3600 will be presented. DEAP-3600 is a single-phase liquid argon (LAr) dark matter detector operating 2 km underground at SNOLAB in Sudbury, Canada. The detector consists of 3.3 tonnes of LAr in a spherical acrylic vessel viewed by an array of 255 photomultiplier tubes. DEAP-3600 has been taking data stably since November 2016. Background events that can mimic dark matter particles' signature can be produced in the detector by different sources including beta/gamma interactions in the LAr and acrylic vessel, neutron-induced nuclear recoils and alpha decays. Analysis of the data taken so far demonstrates the power of pulse shape discrimination (PSD) used to suppress background events. This presentation will feature recent DEAP-3600 performance results, the status of the background model, and the most sensitive limit on WIMP dark matter search using a LAr target. This result is reinterpreted with a more general Non-Relativistic Effective Field Theory (NREFT) framework where DEAP-3600 has leading sensitivity for some model parameters. In addition, we also explore how various possible sub-structures in the local dark matter halo may affect the constraints on WIMP-nucleon interactions.

Speaker: Guillaume Oliviéro (Carleton University)

Oliviero_DEAP_EPS-HEP_talk_2021.pdf

245 DarkSide-20k and the Future Liquid Argon Dark Matter Program

DarkSide run since mid 2015 a 50-kg-active-mass dual phase Liquid Argon Time Projection Chamber (TPC), filled with low radioactivity argon from an underground source and produced world class results for both the low mass ($M_{WIMP} <20GeV/c^2$ ) and high mass ($M_{WIMP}>100GeV/c^2$) direct detection search for dark matter.
The next stage of the DarkSide program will be a new generation experiment involving a global collaboration from all the current Argon based experiments. DarkSide-20k, is designed as a 20-tonne fiducial mass dual phase Liquid Argon TPC with SiPM based cryogenic photosensors, and is expected to be free of any instrumental background for an exposure of >100 ton x years. Like its predecessor DarkSide-20k will be housed at the INFN Gran Sasso (LNGS) underground laboratory, and it is expected to attain a WIMP-nucleon cross section exclusion sensitivity of $7.4\times 10^{-48}\, cm^2$ for a WIMP mass of $1 TeV/c^2$ in a 200 t yr run. DarkSide-20k will be installed inside a membrane cryostat containing more than 700 t of liquid argon and be surrounded by an active neutron veto based on a Gd-loaded acrylic shell. The talk will give the latest updates of the ongoing R\&D and prototype tests validating the initial design.
A subsequent objective, towards the end of the next decade, will be the construction of the ultimate
detector, ARGO, with a 300 t fiducial mass to push the sensitivity to the neutrino floor region for high mass WIMPs.

Speaker: Bianca Bottino

EPS2021_Bottino_final.pdf

T04: Neutrino Physics: Sterile neutrinos

Conveners: Justyna Lagoda (NCBJ), Stefania Bordoni (Université de Genève)

246 Search for light sterile neutrinos with the KATRIN experiment

I will report on the light sterile neutrino search from the first science runs of the KATRIN experiment. Beta-decay electrons from a high-purity gaseous molecular tritium source are analyzed by a high-resolution MAC-E filter down to 40 eV below the endpoint at 18.57 keV. The analysis of the spectral shape of the spectrum near the endpoint leads to an improvement over the previous direct measurement of the neutrino mass, with a published new upper limit of 1.1 eV at 90% C.L. Analyzing the shape of the whole spectrum down to 40 eV below the endpoint, we find no significant distortion compared to the standard model expectation. Therefore, exclusion bounds on the sterile mass and mixing are reported. These new limits supersede the Mainz results and improve the Troitsk bound. The reactor and gallium anomalies are further constrained.

Speaker: Thierry Lasserre (cea)

KATRIN-KSN1-EPSHEP2021.pdf

247 Status of the Short-Baseline Near Detector at Fermilab

The Short-Baseline Near Detector (SBND) will be one of three liquid Argon Time Projection Chamber (LArTPC) neutrino detectors positioned along the axis of the Booster Neutrino Beam (BNB) at Fermilab, as part of the Short-Baseline Neutrino (SBN) Program. The detector is currently in the construction phase and is anticipated to begin operation in the second half of 2022.  SBND is characterised by superb imaging capabilities and will record over a million neutrino interactions per year. Thanks to its unique combination of measurement resolution and statistics, SBND will carry out a rich program of neutrino interaction measurements and novel searches for physics beyond the Standard Model (BSM). It will enable the potential of the overall SBN sterile neutrino program by performing a precise characterisation of the unoscillated event rate, and by constraining BNB flux and neutrino-Argon cross-section systematic uncertainties. In this talk, the physics reach, current status, and future prospects of SBND are discussed.

Speaker: Diana Patricia Mendez (Brookhaven National Laboratory)

SBND_EPSHEP2021_DianaMendez.pdf

248 Short-Baseline neutrino oscillation searches with the ICARUS detector

The ICARUS collaboration employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratories studying neutrino oscillations with the CNGS neutrino beam from CERN, and searching for atmospheric neutrino interactions. ICARUS performed a sensitive search for LSND-like anomalous νe appearance in the CNGS beam, which contributed to the constraints on the allowed parameters to a narrow region around 1 eV$^2$, where all the experimental results can be coherently accommodated at 90% C.L. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 cryogenic commissioning began with detector cool down, liquid Argon filling and recirculation. ICARUS has started operations and is presently in its commissioning phase, collecting the first neutrino events from the Booster Neutrino Beam and the NuMI off-axis. The main goal of the first year of ICARUS data taking will then be the definitive verification of the recent claim by NEUTRINO-4 short baseline reactor experiment both in the $\nu_\mu$ channel with the BNB and in the $\nu_e$ with NuMI. After the first year of operations, ICARUS will commence its search for evidence of a sterile neutrino jointly with the SBND near detector, within the Short Baseline Neutrino (SBN) program. The ICARUS exposure to the NuMI beam will also give the possibility for other physics studies such as light dark matter searches and neutrino-Argon cross section measurements. The proposed contribution will address ICARUS achievements, its status and plans for the new run at Fermilab and the ongoing developments of the analysis tools needed to fulfill its physics program.

Speaker: Filippo Varanini (INFN Padova)

VaraniniEPS2021Final.pdf

249 New results from the DANSS experiment

We present new results of the DANSS experiment on the searches for sterile neutrinos. They are based on 4 million inverse beta decay events collected at 10.9, 11.9, and 12.9 meters from the reactor core of the 3.1 GW Kalinin Nuclear Power Plant in Russia. The neutrino spectrum dependence on the fuel composition is also presented. We have also measured the reactor power using the IBD event rate during 38 months with a statistical accuracy 1.5% in 2 days and with the relative systematic uncertainty of about 0.5%. The status of the DANSS upgrade will be presented. This upgrade should allow DANSS to test the Neutrino-4 claim of observation of sterile neutrinos.

Speaker: Mikhail Danilov (LPI)

Danilov_EPS21v7.pdf

250 Recent results of the SoLid experiment

The SoLid experiment intends to search for active-to-sterile anti-neutrino oscillations at the very short baseline (6.3-8.9 m) of the SCK•CEN BR2 research reactor (Mol, Belgium) to address the so-called “Reactor Anti-neutrino Anomaly”. This anomaly arose from the reevaluation of the predicted reactor anti-neutrino flux which resulted in a deficit observed by very short baseline experiments. This deficit could be explained by flavor oscillations to a new type of neutrino: the sterile neutrino.

High experimental sensitivity to inverse beta decay interactions can be achieved thanks to the innovative combination of highly segmented PVT scintillator that will serve as neutrino target and to measure the positron with a high neutron-gamma discrimination 6LiF:ZnS(Ag) scintillator. This technology offers precise time and space localization of the IBD signals. The reconstruction of the full topology of the events allows a strong background rejection, necessary given the low overburden at the reactor building and the presence of 214BiPo background from the 238U decay chain in the neutron screens. From the analysis point of view many variables can be reconstructed and exploited with multivariates and boosted decision trees analysis to improve the background rejections.

The detector has been taking a first phase of physics data from 2018 to 2020. In this contribution we will present an overview of the experiment, the background rejections capabilities, the extraction of the reactor anti-neutrino signal and in particular for the first time the physics results with two years of data. The ability to probe the RAA with this result will be investigated. Finally the perspective of a full event topology analysis will be presented on the first opened dataset of 2018.

Speaker: Shingo HAYASHIDA

Recent Results of the SoLid Experiment - EPS-HEP2021.pdf

251 New physics from oscillations: sensitivity for the DUNE near detector

We study the capabilities of the DUNE near detector to probe deviations from unitarity of the leptonic mixing matrix, the 3+1 sterile formalism and NSI in detection and production, clarifying the relation and possible mappings among the three formalisms. We add to the current analyses in the literature the use of the charged current events for the ντ appearance channel and the consideration of the energy spectral uncertainty (shape uncertainty) of the background. We find that this plays an important role on the results, and is usually overlooked in the literature. Even with this more conservative and realistic approach, we still obtain an improvement in the sensitivity with respect to the current bounds.

Speaker: Salvador Urrea (González)

EPS-HEP2021talk-New-physics-from-oscillations-Dune-ND

T05: Heavy Ion Physics: Part 4

Note: All contributions are given 12 minutes + 3 min for questions

252 Constraining transport properties of quark-gluon plasma using non-linear hydrodynamic response

The primary goal of the ultrarelativistic heavy-ion collision program at the LHC is to study the properties of the quark-gluon plasma (QGP), a state of strongly interacting matter that exists at high temperatures and energy densities. Anisotropic flow, studied using the anisotropy of the momentum distribution of final state particles, is sensitive to the transport properties (i.e., specific viscosities) of the QGP. It $v_{n}$ contains two components, the linear mode corresponds to the same order initial anisotropy coefficient while the non-linear flow mode is originated from lower-order initial anisotropy. It is commonly known that the lower order flow $v_{2}$ and $v_{3}$ have the linear response for non-peripheral collisions and therefore can be used directly to constrain the initial state models, while the study of linear and non-linear flow modes of higher-order flow has the potential to improve the accuracy of the extracted transport coefficients of QGP.

In this talk, the latest studies of the non-linear hydrodynamic response of anisotropic flow in Pb--Pb collisions at the LHC will be presented. The new studies using higher-order moments of $v_{2}$, as well as the newly proposed correlations between different moments of $v_{2}$ and $v_{3}$, show an unexpected non-linear response of $v_{2}$ and $v_{3}$ in the semi-central and semi-peripheral collisions. In addition, the non-linear hydrodynamic response has been explored via the correlations among multiple flow coefficients. These systematic studies using hybrid hydrodynamic iEBE-VISHNU with two different initial conditions, AMPT and TRENTo, and using AMPT and HIJING transport models, show that such non-linear hydrodynamic response has novel sensitivity to the specific viscosities of QGP. The comparisons of state-of-the-art hydrodynamic calculations and the recently available ALICE measurements offer new insights into the transport properties and the dynamical evolution of the QGP.

References:

$[1]$ Z Moravcova, K. Gulbrandsen, Y. Zhou, Physical Review C 103, 024913 (2021)

$[2]$ M. Li, Y. Zhou, W. Zhao, B. Fu, Y. Mou and H. Song, arXiv: 2104.10422

Speaker: Zuzana Moravcova (Niels Bohr Institute)

EPS_ZM.pdf

253 Anisotropic flow decorrelation in heavy-ion collisions at RHIC-BES energies with 3D event-by-event viscous hydrodynamics

In the RHIC Beam Energy Scan program, gold nuclei are collided with different collision energies in the range from few to 62.4 GeV. The goals of the program are to explore the onset of QGP creation, locate the critical point of QCD and study dense baryon matter.
In this talk, we report on the first application of 3D Monte Carlo Glauber (GLISSANDO2) and TrENTO p=0 initial states for 3D event-by-event viscous fluid dynamic (vHLLE) + cascade modelling of Au+Au collisions at $\sqrt{s_{\rm NN}}=27$ and 62.4 GeV, which is the upper region of RHIC BES energies. The initial states are extended into both the longitudinal direction and for finite baryon density using simple ansätze. The full energy and baryon charge counting in the initial states is implemented. We show the reproduction of basic hadronic observables - pseudorapidity distributions of charged hadrons and net protons, transverse momentum spectra and elliptic flow, at both collision energies and with both initial states. We compare it to the existing results obtained with UrQMD initial state.
Furthermore, we show the results for rapidity decorrelation of elliptic flow $r_2$ at $\sqrt{s_{\rm NN}}=27$ and 200 GeV from the same setup of hydrodynamic calculations with the 3D Monte Carlo Glauber and UrQMD initial states. We discuss the features of the initial states responsible for the magnitude of the observed flow decorrelation, and the effect of the final-state hadronic cascade.
Publication reference: Phys. Rev. C 103, 034902 (2021)

Speaker: Jakub Cimerman (Czech Technical University in Prague)

Cimerman_EPS-HEP2021_talk.pdf

254 Measurement of the jet-particle $v_2$ in p–Pb and Pb–Pb collisions at $\sqrt{s_{\rm NN}}=$ 5.02 TeV with ALICE at the LHC

In heavy-ion collisions, the observed non-zero second-order azimuthal anisotropy coefficient $v_2$ of particles with high transverse momenta $p_{\rm T}$ is driven by the path-length dependent energy loss of hard partons traveling in the quark-gluon plasma, known as the jet quenching effect. Recent measurements show also a non-zero $v_2$ value for high-$p_{\rm T}$ charged particles at high multiplicities in small collision systems. The origin of this effect is still debated, and various mechanisms, such as parton energy loss in the cold nuclear matter, hydrodynamic evolution in the final state and initial-state gluon correlations, are proposed to describe the observations. In this contribution, the $v_2$ measurements of charged particles in jets at midrapidity (|η|<0.8) in 20–60% semicentral Pb–Pb collisions and 0–10% most central p–Pb collisions at $\sqrt{s_{\rm NN}} =$ 5.02 TeV recorded with the ALICE detector are presented. The particles associated with jets are extracted from the two-particle correlations using a combined fit, and their $v_2$ are calculated with the scalar product method in Pb–Pb collisions and the central-forward correlation method in p–Pb collisions. The comparisons of the jet-particle and inclusive-particle $v_2$ in both p–Pb and Pb–Pb collisions will bring new insight into the understanding of the origin of the high-$p_{\rm T}$ azimuthal anisotropy observed in small collision systems.

Speaker: Siyu Tang

EPS2021.pdf

255 The Gluon Exchange Model for diffractive and inelastic collisions

We propose a new model for a homogeneous description of hadron-hadron and hadron-nucleus collisions, the Gluon Exchange Model (GEM). While technically our model can be regarded as a generalization of the Dual Parton Model by Capella and Tran Thanh Van, it is fundamentally based on the number of exchanged color octets (gluons) and significantly extends the Fock space of states available for the participating protons and nucleons.

In proton-proton collisions we provide an exact description of the final state proton and neutron spectrum. What is remarkable is that unlike the original DPM, GEM successfully describes the proton “diffractive peak” at high $x_F$ as a specific case of color octet exchange.

In proton-nucleus reactions we find that the projectile proton diquark cannot survive in more than about half of multiple proton-nucleon processes and consequently must be very frequently disintegrated, leading to long transfers of baryon number over rapidity space.

This talk will be partially based on our recent paper, Phys. Lett. B 816 (2021) 136200, e-Print: 2101.01999 [nucl-th]

Speaker: Marek Jeżabek (Institute of Nuclear Physics, Polish Academy of Sciences)

Jeżabek_Rybicki_EPSHEP2021.pdf

256 Measurement of electroweak-boson production in pp, p-Pb, and Pb-Pb collisions with ALICE at the LHC

W and Z boson measurements provide a clean probe of the hard scatterings taking place in the initial stages of hadronic collisions. In particular, measurements in pp collisions provide a useful reference to test pQCD calculations, while results in p-Pb and Pb-Pb collisions provide a useful insight in the nuclear parton distribution functions (nPDFs) of the involved nuclei. Such observations are especially important in a phase space region that is poorly constrained by previous experiments, and represent an important reference to properly understand nuclear modification effects in other measurements. In this contribution the most recent measurements on W and Z boson production by the ALICE collaboration are discussed, including invariant production yields and nuclear modification factors. W and Z bosons are measured in ALICE via their leptonic decays in the electron channel at midrapidity ($|\eta_\mathrm{lab}| < 0.8$) and the muon channel at forward rapidity ($2.5 < \eta_\mathrm{lab} < 4$). New measurements on W bosons in pp collisions at $\sqrt{s} = 13$ TeV are presented, as well as the latest results on Z and W bosons in p-Pb collisions at $\sqrt{s_\mathrm{NN}} = 8.16$ TeV and Pb-Pb collisions at $\sqrt{s_\mathrm{NN}} = 5.02~{\rm TeV}$. Differential measurements as a function of rapidity and collision centrality are compared to previous experimental results and to the available theoretical calculations, providing constraints on the corresponding models and the considered nPDFs.

Speaker: Shingo Sakai

EPS_WZ_ssakai.pdf

257 Electron-Ion Collisions at the LHeC and FCC-he

The LHeC and the FCC-he will open a new realm in our understanding of nuclear structure and the dynamics in processes involving nuclei, in an unexplored kinematic domain. In this talk we will review the most recent studies as shown in the update of the 2012 CDR [1]. We will discuss the determination of nuclear parton densities in the framework of global fits and for a single nucleus. Then we will discuss diffraction, both inclusive and exclusive. Finally we will demonstrate the unique capability of these high-energy colliders for proving the long sought non-linear regime of QCD, saturation, to exist (or to disprove). This is enabled through the simultaneous measurements, of similar high precision and range, of $ep$ and $e$A collisions which will eventually disentangle non-linear parton-parton interactions from nuclear environment effects.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e Print: 2007.14491 [hep-ex], to appear in J. Phys. G.

Speaker: Guilherme Milhano

LHeC_ MILHANO.pdf

258 A large bound state in small systems: ALICE measurement of hypertriton production in pp and p-Pb collisions

The study of (anti)nuclei production in hadronic collisions has proven to be a powerful tool to investigate the formation mechanism of loosely bound states. The $^{3}_{\Lambda}\text{H}$ is a bound state of Λ, proton, and neutron characterised by a Λ separation energy of few keV, which leads to a large wave function. As a consequence, the measured (anti-)$^{3}_{\Lambda}\text{H}$ production yields in pp and p-Pb collisions can resolve the difference between the Statistical Hadronisation Model (SHM) predictions, which are insensitive to the $^{3}_{\Lambda}\text{H}$ structure, and the coalescence model.

In this talk the first measurements of the production of (anti-)$^{3}_{\Lambda}\text{H}$ in pp and p-Pb collisions are presented. In this context, the measurements are compared with the expectations of coalescence and SHM. With the precision of the presented measurements, ALICE is setting tighter constraints to available theoretical models, in particular excluding some configurations of the Statistical Hadronisation and Coalescence models.

Speaker: Janik Ditzel

Hypertriton_JD_EPS2021_final.pdf

259 Nuclear coalescence and collective behaviour in small interacting systems

The production of light nuclei in particle collisions can be described as the coalescence of nucleons into nuclei. In most coalescence models used in heavy ion collisions, the probability for coalescence is controlled predominantly by the size of the interaction region, while nucleon momentum correlations may be treated as collective flow or even neglected. Interestingly, recent experimental data on pp collisions at LHC have been interpreted as evidence for such collective behaviour even in small interacting systems. This is contradiction to the standard approach of imposing the coalescence condition only in momentum space for small interacting systems, such as e+e- and dark matter annihilations or pp collisions. We argue however that these data are naturally explained using QCD inspired event generators when taking into account both nucleon momentum correlations and the size of the hadronic emission volume. To consider both effects, we use a per-event coalescence model based on the Wigner function representation of the produced nuclei states. This model reproduces well the size of baryon-emitting source as well as the coalescence factor B2 recently measured in pp collisions by the ALICE collaboration. Finally, we comment on the generalisation to larger interacting systems.

Speaker: Jonas Tjemsland (NTNU)

tjemsland.pdf

T06: QCD and Hadronic Physics: Part 4: Quarkonia and heavy flavour

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Daniel Johnson (CERN)

260 Quarkonium production in pp, p-Pb, and peripheral Pb-Pb collisions with ALICE (12'+3')

The production of quarkonia, bound states of heavy quark-antiquark pairs, in hadronic collisions is a unique testing ground for our understanding of QCD as the theory of the strong interaction. The hard scattering that produces the heavy-quark pair can be described within perturbative QCD, whereas the evolution of this pair into a colorless bound state involves soft scales. At LHC energies, quarkonia are abundantly produced, and hence can be used to investigate multiple parton interactions. In addition, in pp collisions, quarkonium production serves as a reference for the production in proton-nucleus and nucleus-nucleus collisions, where it becomes sensitive to cold nuclear matter effects (nuclear shadowing of the parton density, energy loss of the $q\bar{q}$ pair while traversing the nucleus, rescattering/break-out effects) and hot nuclear effects (QGP formation). Furthermore in peripheral Pb-Pb collisions, J/$\psi$ photoproduction in coincidence with hadronic interaction can probe the initial state of the heavy-ion collision. ALICE is able to measure quarkonia both at forward (2.5 $< y <$ 4) and midrapidity ($|y| <$ 0.9) down to zero transverse momentum in all collision systems provided by the LHC, which is a unique feature. In this contribution, final results in pp collisions on J/$\psi$, $\psi$(2S), and $\Upsilon$(nS) production at forward rapidity at $\sqrt{s}$ = 5.02 TeV, and on J/$\psi$ production at midrapidity at $\sqrt{s}$ = 5.02 and 13 TeV will be presented. At midrapidity, the prompt J/$\psi$ production, originating from direct quarkonium production in the collision, and the non-prompt J/$\psi$ production, originating from b-hadron decays are measured separately. Inclusive J/$\psi$ cross section is measured at midrapidity up to 40 GeV/$c$ at $\sqrt{s}$ = 13 TeV, thanks to events triggered according to the energy deposition in EMCAL. Results on the hadron multiplicity dependence of J/$\psi$ production at $\sqrt{s}$ = 5.02 and 13 TeV at both central and forward rapidities, and preliminary results on the multiplicity dependence of $\psi$(2S) and $\Upsilon$(1S, 2S) production at forward rapidity at $\sqrt{s}$ = 13 TeV will be shown. In p-Pb collisions, at forward rapidity and $\sqrt{s_{NN}}$ = 8.16 TeV, final results on $\psi$(2S) yield modification, including its dependence on the event centrality and on $\Upsilon$ production will be presented. Finally, we will show new results based on the full Run 2 Pb-Pb statistics on J/$\psi$ photoproduction in hadronic semi-central collisions at forward rapidity. The comparison of results across different beam energies and with theoretical model calculations will also be discussed.

Speaker: Yvonne Pachmayer

Pachmayer_EPS2021.pdf

261 Studies of excited heavy flavor states at CMS (12'+3')

Recent CMS results on spectroscopy of heavy mesons and baryons are reported.

Speaker: Nikita Petrov (Moscow Institute of Physics and Technology (RU))

EPS-HEP2021.pdf

262 Recent results in production of open-charm and charmonium states at LHCb (12'+3')

Speaker: Qingnian Xu (UCAS)

QXu_EPS2021.pdf

263 Charm cross section and fragmentation fractions in pp collisions with ALICE (12'+3')

In this contribution, we present the latest measurements of $\Lambda^{+}_{\rm c}$, $\Xi^{+,0}_{\rm c}$, $\Sigma^{0,++}_{\rm c}$, and the first measurement of $\Omega^{0}_{\rm c}$ baryons performed with the ALICE detector at midrapidity in pp collisions at $\sqrt{s}$ = 5.02 and 13 TeV. Recent measurements of charm-baryon production at midrapidity by the ALICE Collaboration in small systems show a baryon-over-meson ratio significantly higher than that in $e^+e^−$ collisions, suggesting that the fragmentation of charm is not universal across different collision systems. Thus, measurements of charm-baryon production are crucial to study the charm quark hadronisation in proton-proton collisions and its difference with respect to $e^+e^−$ collisions, which is also relevant for the description of heavy-flavour mesons. In fact, the production cross sections of open heavy-flavour hadrons are usually described within the factorisation approach as the convolution of the parton distribution functions of the incoming protons, the perturbative QCD partonic cross section, and the fragmentation functions which are typically parametrised from measurements in $e^+e^−$ collisions. In addition, the large measured baryon yields are an important contribution for an accurate measurement of the $\rm c\overline{c}$ production cross section at midrapidity in pp collisions at the LHC, which status and progresses are also presented. Furthermore, the new $\Lambda^{+}_{\rm c}/{\rm D^{0}}$ratio measured down to $p_{\rm T}$ = 0 in p-Pb collisions as well as the nuclear modification factor will be discussed. The measurement of charm baryons in p-nucleus collisions provides important information about Cold Nuclear Matter (CNM) effects. It also helps to understand how the possible presence of collective effects could modify production of heavy-flavour hadrons and the similarities observed among pp, p-nucleus and nucleus-nucleus systems. The results will be compared to models including CNM effects, as well as models assuming the formation of a quark-gluon plasma in p-Pb collisions.

Speaker: Luigi Dello Stritto (Università degli Studi di Salerno)

ldellost_EPS2021.pdf

264 Charmonium Decays at BESIII (12'+3')

Although the charmonium spectrum seems to be well investigated, charmonia can still be used as benchmarks to test our QCD predictions, as these states lay in the transition region between perturbative and non-perturbative QCD.Despite the need for experimental confirmations, setbacks arise from limited statistics because of the production processes of all non-vector states. The
properties and many decay channels of some charmonium states (such as hc or eta_c(2S)) are still far from being known.
Since 2009, BESIII has been scanning and investigating the charmonium
region to shed light on open questions. Thanks to its unique J/psi; and psi(2S) data sets, BESIII could overcome statistical limitations.
Recent results on charmonium decays from BESIII are presented.

Speaker: Marco Scodeggio (INFN Ferrara)

Charmonium_Decays_BESIII_EPSHEP21_Marco_Scodeggio.pdf

265 Charmed Baryon results from Belle (12'+3')

Precision hadron spectroscopy helps in understanding how the matter is made around us. The large data sample accumulated by the Belle experiment at the KEKB asymmetric-energy $e^{+}e^{-}$ collider provides us a unique opportunity to perform these studies. We report recent results on charmed baryon spectroscopy from Belle, which include a study on the spin and parity of $\Xi_{c}(2970)$ and $\Xi_{c}^{0}$ decays to $\Xi^{0} K^{+} K^{-}$, $\Xi^{-} \ell^{+} \nu_{\ell}$, $\Lambda K^{*}$, and $\Sigma K^{*}$. The talk may also cover results on non-charmed baryons at Belle.

Speaker: Yubo Li (Fudan University)

EPS-HEP2021.pdf

266 Observation of Lambda_b -antiLambda_b production asymmetry (12'+3')

A precise measurement of the Lambda_b production asymmetry is critical to the measurements of CP violation in the decay of b-baryons at LHCb. In general these production asymmetries cannot be precisely predicted since they require knowledge of non perturbative b-quark hadronisation processes, and so need to be experimentally determined. The semileptonic Lambda_b->Lambda_c mu nu decay offers an excellent tool for precise measurement of such production asymmetry. It has a large branching fraction and a clear experimental signature with the presence of a high transverse momentum muon. Furthermore, it is theoretically clean and the CP violation in the decay can be safely assumed to be negligible. The first observation of the Lb-anti-Lb baryon production asymmetry is presented, together with strong evidence of a dependence of this production asymmetry with the rapidity.

Speaker: Laurent Dufour (CERN)

LD_EPS_2021_Lb_production_asymmetry.pdf

267 Bottomonium results and prospects at Belle II (12'+3')

The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is an upgrade of the B factory facility at KEK in Tsukuba, Japan. The experiment began operation in 2019 and aims to record a factor of 50 times more data than its predecessor. Belle II is uniquely capable of studying the so-called "XYZ" particles: heavy exotic hadrons consisting of more than three quarks. First discovered by Belle, these now number in the dozens, and represent the emergence of a new category within quantum chromodynamics. We present recent results in new Belle II data, and the future prospects to explore both exotic and conventional bottomonium physics.

Speaker: Gian Luca Pinna Angioni (Torino)

BottomoniumBelleII.pdf

T08: Flavour Physics and CP Violation: Part 4

Conveners: Jorge Martin Camalich (Instituto de Astrofisica de Canarias), Shikma Bressler (Weizmann Institute of Science)

268 New results on semileptonic $B$ meson decays from the Belle experiment

Though the Belle experiment has stopped data taking more than a decade ago, new results on semileptonic $B$ meson decays are still being obtained. This is in part due to new experimental tools elaborated for Belle II applied to the Belle data set, such as the FEI (Full Event Interpretation) hadronic and semileptonic tag which enables new measurements of $B \to D^{*}\ell\nu$, $B \to D^{\ast\ast}\ell\nu$ and $B \to X\ell\nu$. Other analyses are motivated by the progress in theory such as the measurement of $q^{2}$ moments in $B \to X_{c}\ell\nu$, which allows for a determination of $|V_{cb}|$ up to the order $1/m_{b}^{4}$. This talk covers all new semileptonic $B$ decay results obtained with the Belle data set.

Speaker: Lu Cao (FH (Forschung Hochenergiephysik))

EPS_LuCao_Jul2021.pdf

269 Towards first $V_{ub}$ and $V_{cb}$ measurements at the Belle II experiment

Precision determinations of $V_{ub}$ and $V_{cb}$ play a central role in precision tests of the CKM sector of the Standard Model and complement direct measurements of CP violation of B meson decays. In this talk, we present first studies towards measurements of $|V_{ub}|$ and $V_{cb}$, with semileptonic decays using collision events recorded at the $\Upsilon(4S)$ resonance by the Belle II experiment. We report the status of measuring branching fractions and kinematic properties of inclusive and exclusive $b \to u \ell \bar \nu_\ell$ and $b \to c \ell \bar \nu_\ell$ decays using untagged and tagged approaches in the full available Belle II data set. In addition, we present a Belle II measurement of the $q^2$ moments of $B \rightarrow X_{c} \ell \nu$ decay. The $q^2$ moments of the $b \rightarrow c \ell \nu$ transition are particularly powerful for constraining the Heavy Quark Expansion as they can be expressed in terms of a reduced set of matrix elements due to reparametrization invariance.

Speaker: Mario Merola (INFN and Univ. Napoli)

VubVcb_MEROLA_EPS2021.pdf

270 BaBar B ->D*lnu amplitude analysis confronting latest lattice data

We present comparisons between the results obtained in the BaBar B ->D*lnu amplitude analysis (PRL 123, 091801 (2019)) in the light of new non-zero recoil lattice data from MILC. We also discuss prospects for probing right-handed currents from a joint lattice + BaBar fit, in a manner independent of the |Vcb| normalization issue.

Speaker: Biplab Dey

BaBar_Dstlnu_Biplab.pdf

271 Form factors for semileptonic B(s) decays

Determinations of the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$ or predictions for $R$-ratios testing lepton flavor universality can be obtained from form factors describing exclusive semileptonic $B_{(s)}$ decays. Using the framework of lattice quantum chromodynamics, we report on our form factor calculations for $B_s\to D_s \ell\nu$, $B_s\to K \ell\nu$, and $B\to \pi\ell \nu$ decays. First scalar and vector form factors with full error budget are presented for the range of momentum transfer directly accessible in our simulations. Next we show $z$-parameterization fits to extend $q^2$ over the kinematically allowed range and use the results to extract CKM matrix elements or predict $R$-ratios.

Our calculations are based on RBC-UKQCD's set of 2+1 flavor domain wall Iwasaki gauge field configurations featuring three lattice spacings of $a^{-1}$ = 1.78, 2.38, and 2.78 GeV. We simulate up/down, strange, and charm quarks using domain-wall fermions and use the relativistic heavy quark action for the bottom quarks.

Speaker: Oliver Witzel (Universität Siegen)

witzel_oliver.pdf

272 Updated Predictions for $R(D^{(*)})$ within and beyond the Standard Model and determination of $|V_{cb}|$

In Heavy Quark Effective Theory (HQET), measured $B \to D^{(*)} \ell \bar \nu_\ell$ decay rates for light leptons constrain all $B \to D^{(*)}$ semileptonic form factors, both in and beyond the Standard Model (SM). We update our prior HQET-based analysis, carrying out a global fit including newly available measurements of $B \to D^{(*)} \ell \bar \nu_\ell$ decay distributions to predict: the $B \to D^{(*)} \tau \bar \nu_\tau$ rates; the lepton universality ratios $R(D^{(*)})$ within and beyond the SM; and determine the CKM matrix element $|V_{cb}|$. The update incorporates a more systematic treatment of certain corrections at order $1 / m_{c}^2$, and discusses the impact of including preliminary lattice QCD information for $B \to D^{(*)}$ form factor ratios from JLQCD.

Speaker: Florian Bernlochner (BELLE (BELLE II Experiment))

BLPR_XP.pdf

273 Measurement of semitauonic b-hadron decays

The semileptonic b-hadron decays with a heavy lepton are sensitive to new couplings like those generated by charged Higgses or Leptoquarks. The B-Factories and LHCb have previously performed various measurements of these decays, using different approaches and techniques. A global average of these measurements shows a discrepancy with the Standard Model expectations, which is above 3 standard deviations. A measurement of the combined ratios BF(B->D tau nu)/BF(B->D mu nu) and BF(B->D tau nu)/BF(B->Dmu nu) using 3/fb collected by LHCb in Run1, is presented.

Speaker: Biljana Mitreska (University of Manchester (GB))

EPS_2021_Mitreska_v4.pdf

274 A new determination of $|V_{cb}|$ using inclusive $q^2$ moments of $B \to X_c \ell \bar \nu_\ell$ decays

Precision determination of the CKM matrix element $|V_{cb}|$ are important to test the unitarity of the CKM matrix and to search for loop-level new physics effects. In this talk, we present a new determination of $|V_{cb}|$ using measured $q^2$ moments from $B \to X_c \ell \bar \nu_\ell$ decays provided by the Belle and Belle II collaborations. This new experimental input is the key ingredient to determine the non-perturbative hadronic matrix elements entering the total semileptonic $B \to X_c \ell \bar \nu_\ell$ rate in the heavy-quark expansion. Exploiting reparametrization invariance, the number of these non-perturbative parameters can be reduced to 8 at $\mathcal{O}(1/m_b^4)$. The value of these parameters and $|V_{cb}|$ is simultaneously determined, taking into account also the theoretical uncertainties from missing higher order contributions in the heavy quark expansion and corrections from the strong interaction.

Speaker: Kevin Olschewsky

275 CKM parameter measurement with semileptonic Bs decay at LHCb

The long standing discrepancy between determinations of the CKM matrix element Vub obtained from exclusive and inclusive semileptonic B decays are at the level of 2-3 standard deviations. This discrepancy continues to challenge our understanding of the semileptonic decays on both the theoretical and experimental sides. Exclusive semileptonic Bs decays are in principle under good theoretical control and provide complementary information with respect to the B-factories in this sector. The first observation of the decay Bs->K mu nu is reported. Using the measurement of the Bs->K mu nu branching fraction relative to the well known Bs->Ds mu nu decay, and the most recent theoretical knowledge of the relevant Bs decays form factors, the ratio of CKM matrix elements Vub/Vcb is extracted, with a precision competitive with the existing measurements. However, the regions of high and low momentum transfer, show inconsistent results. Further investigations are needed to solve the observed discrepancy.

Speaker: Anna Lupato (The University of Manchester)

eps2021_rev1.pdf

T09: Higgs Physics: double-Higgs production and self-coupling

Conveners: Sarah Heim (DESY), meng xiao (zhejiang university), Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris), Michael Trott (NBI)

276 Searches for Higgs boson pair production with the full LHC Run-2 dataset in ATLAS

The latest results on the production of Higgs boson pairs (HH) in the ATLAS experiment are reported, with emphasis on searches based on the full LHC Run 2 dataset at 13 TeV. In the case of non-resonant HH searches, results are interpreted both in terms of sensitivity to the Standard Model and as limits on kappa_lambda, i.e. a modifier of the Higgs boson self-coupling strength. Searches for new resonances decaying into pairs of Higgs bosons are also reported. Prospects of testing the Higgs boson self-coupling at the High Luminosity LHC (HL-LHC) will also be presented.

Speaker: Valentina Cairo (SLAC National Accelerator Laboratory)

EPS_HH_ATLAS_VMMCAIRO_27July2021.pdf

277 Searches for non-resonant and resonant HH production at CMS

Recent CMS results on HH, X->HH and X->HY production will be presented.

Speaker: Agni Bethani (Universite Catholique de Louvain (UCL) (BE))

HHEPSAgni_Presented.pdf

278 Two-loop corrections to the Higgs trilinear coupling in classically scale-invariant theories

The Higgs trilinear coupling provides a unique opportunity to probe the structure of the Higgs sector and the nature of the electroweak phase transition, and to search for indirect signs of New Physics. Classical scale invariance (CSI) is an attractive concept for BSM model building, explaining the apparent alignment of the Higgs sector and potentially relating to the hierarchy problem. A particularly interesting feature of CSI theories is that, at one loop, they universally predict the Higgs trilinear coupling to deviate by 67% from the (tree-level) SM prediction.
In this talk, I will show how this result is modified at two loops. I will present results from the first explicit computation of two-loop corrections to the Higgs trilinear coupling in classically scale-invariant BSM models. Taking as example a CSI variant of a Two-Higgs-Doublet Model, I will show that the inclusion of two-loop effects allows distinguishing different scenarios with CSI, even though the requirement of correctly reproducing the mass of the Higgs boson severely, as well as unitarity, restrict the allowed values of the Higgs trilinear coupling.

Speaker: Johannes Braathen (T (Phenomenology))

Braathen_EPSHEP2021.pdf

279 NLO production of HH, ZH, and ZZ by gluon fusion, in the high-energy limit

In this talk I will discuss computations of NLO virtual corrections to
four-point gluon-fusion processes; in particular the production of HH,
ZH and ZZ. Recently these processes have been computed numerically, but
they are not known analytically. I will discuss how one can perform an
expansion of these amplitudes in the high-energy limit, and improve the
resulting series through the use of Padé approximants.

Speaker: Joshua Davies (University of Sussex)

davies.pdf

280 Machine learning augmented probes of light Yukawa couplings from Higgs pair production

The production of Higgs pairs is one of the most anticipated channels to access at the High-Luminosity LHC. It allows for a measurement of the Higgs trilinear self-interaction. In this work we investigate the possibility to probe the Higgs trilinear coupling through the decomposition of the Higgs pair production into channels based on their topologies. We use interpretable machine learning based on cooperative game theory in order to distinguish them, simplifying the machine learning analysis flow. This procedure ultimately leads to a strong bound on the trilinear coupling. Moreover, we extend the analysis by including the quark-initiated channel, $q\bar{q}\to hh$, which is strongly suppressed in the Standard Model, in order to probe the Higgs coupling to light quarks. We perform a multivariate fit to simultaneously extract the trilinear Higgs and light quark-Higgs couplings. The fit results in a loosened bound on the trilinear coupling by $\sim 25$\% for models that do not have minimal flavour violation. Furthermore, a similar analysis is preformed for the 100 TeV FCC-hh. We discuss some motivated new physics scenarios where large modifications in the light quark-Higgs couplings are manifest.

Speaker: Lina Alasfar (Humboldt Universität zu Berlin)

EPS-HEP-21_talk-reduziert.pdf

281 Higgs self-coupling measurements in the HL-LHC era: new approaches for the HH->4b final state.

Searches for pairs of Higgs bosons will  be, in all likelihood, the best tools to precisely measure the Higgs boson self-coupling $\lambda_{hhh}$ in future colliders. We study various strategies for the $hh\to b \bar{b} b \bar{b}$ search in the HL-LHC era with focus on constraining $\lambda_{hhh}$. We implement a machine-learning-based approach to separate signal and background and apply recent advances in machine learning interpretability, compare the traditional 4 $b$-jet reconstruction to final states with 1 or 2 large-radius jets, and test scenarios with different top-quark Yukawa couplings, among other factors.
Based on arXiv:2004.04240.

Speaker: Santiago Paredes Saenz (Université Libre de Bruxelles)

eps_hh4b.pdf

282 Large triple Higgs couplings in the 2HDM

An important task at future colliders is the investigation of the Higgs-boson sector. Within the framework of the $CP$ conserving Two Higgs Doublet Models (2HDM) type I and II we investigate the allowed ranges for all triple Higgs couplings involving at least one light, SM-like Higgs boson. We will define and explore some benchmark planes that show large values of triple Higgs couplings, still in agreement with all the relevant theoretical and experimental constraints. We find that the SM-type triple Higgs coupling w.r.t. its SM value, $\kappa_{\lambda}:=\lambda_{hhh}/\lambda_{\mathrm{SM}}$, can range between $\sim-0.5$ and $\sim1.5$ in type I and between $\sim0$ and $\sim1$ in type II. We find the coupling $\lambda_{hhH}$ between $\sim\pm$1.5 and triple Higgs couplings involving two heavy Higgs bosons, $\lambda_{hHH}$, $\lambda_{hAA}$ and $\lambda_{hH^{+}H^{-}}$ can reach values up to $O(10)$, roughly independent of the 2HDM type. Finally, we will comment on the possible phenomenological consequences of this results, focusing on double Higgs production in future $e^{+}e^{-}$ colliders.

Speaker: Francisco Arco Garcia (Instituto de Física Teórica (IFT-UAM))

Slides_EPS.pdf

T10: Searches for New Physics: Part 4

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Marija Vranjes Milosavljevic (Institute of Physics Belgrade)

283 Searches for new physics with leptons using the ATLAS detector

Many theories beyond the Standard Model predict new phenomena, such as Z’, W’ bosons or heavy neutrinos, in final states with isolated, high-pt leptons (e/mu/tau). Searches for new physics with such signatures, produced either resonantly or non-resonantly, including a general search using multilepton final states are performed using the ATLAS experiment at the LHC. Lepton flavor violation (LVF) is a striking signature of potential beyond the Standard Model physics. The search for LFV with the ATLAS detector is reported in searches focusing on the decay of the Z boson into different flavour leptons (e/mu/tau). The recent 13 TeV pp results will be reported.

Speaker: Daniele Zanzi (Freiburg)

EPS_zanzi.pdf

284 Searches for new physics in CMS in events with leptons and photons in the final state

Many new physics models, e.g., compositeness, extra dimensions, extended Higgs sectors, supersymmetric theories, and dark sector extensions, are expected to manifest themselves in the final states with leptons and photons. This talk presents searches in CMS for new phenomena in the final states that include leptons and photons, focusing on the recent results obtained using the full Run-II data-set collected at the LHC.

Speaker: Jan-Frederik Schulte (Purdue University (US))

EPS2021_CMSLeptonPhotonSearches_JSchulte.pdf

285 Searches for new physics in CMS in events with jets in the final state

Many new physics models, e.g., compositeness, extra dimensions, excited quarks, and dark matter mediators, are expected to manifest themselves in final states with jets. This talk presents searches in CMS for new phenomena in the final states that include jets, focusing on the recent results obtained using the full Run-II data-set collected at the LHC.

Speaker: Magda Diamantopoulou

EPS2021_V3.pdf

286 Dark Sector searches in CMS

New physics may have gone unseen so far due to it being hidden in a dark sector. This may result in a rich phenomenology which we can access through portal interactions. In this talk, we present recent results from dark-sector searches in CMS using the full Run-II data-set of the LHC.

Speaker: Annapaola de Cosa (ETHZ)

deCosa_DarkSectorCMS.pdf

287 Characterising darkjets: Implications of theory scenarios for experimental signatures

Scenarios of strongly interacting dark matter, where confinement in a new non-abelian dark sector leads to composite dark matter candidate are increasingly at the focus of LHC searches. These scenarios where bound state masses are low compared to the LHC scale lead to exotic darkjet signatures such as semi-visible, emerging jets. With the example of an SU(Nd) gauge group, we present the impact of variation of number of dark flavours, colours, bound state masses, mediator lifetime as well as mediator decay mode along with other theory parameters on the properties of resulting dark jets. With these investigations, we illustrate potential strategies useful for defining inclusive darkjet searches at the LHC.

Speaker: Suchita Kulkarni (University of Graz)

Kulkarni_EPS.pdf

288 Searching for pseudo-Nambu-Goldstone boson dark matter production in association with top quarks

Pseudo-Nambu-Goldstone bosons (pNGBs) are attractive dark matter (DM) candidates since they are coupled to the Standard Model (SM) predominantly through derivative interactions. Thereby, they naturally evade the strong existing limits inferred from DM direct detection experiments. Working in an effective field theory that includes both derivative and non-derivative DM-SM operators, we perform a detailed phenomenological study of the Large Hadron Collider reach for pNGB DM production in association with top quarks. Drawing on motivated benchmark scenarios as examples, we compare our results to other collider limits as well as the constraints imposed by DM (in)direct detection experiments and the relic abundance. Furthermore, we explore implications on the viable parameter space of pNGB DM. In particular, we demonstrate that the sensitivity of DM direct detection experiments can be achieved via loop-induced interactions. The search strategies we discuss can serve as a starting point for dedicated experimental analyses by the ATLAS and CMS collaborations.

Speaker: Stefan Schulte (Max Planck Institute for Physics (Munich))

Schulte_EPSHEP2021.pdf

289 Blast from the past: Constraints on the dark sector from the BEBC WA66 beam dump experiment

We derive limits on millicharged dark states, as well as particles with electric or magnetic dipole moments, from the number of observed forward electron scattering events at the Big European Bubble Chamber in the 1982 CERN-WA-066 beam dump experiment. The dark states are produced by the 400 GeV proton beam primarily through the decays of mesons produced in the beam dump, and the lack of excess events places bounds extending up to GeV masses. These improve on bounds from all other experiments, in particular CHARM II.

Speaker: Mr Giacomo Marocco (University of Oxford)

main.pdf

290 Search for heavy neutral lepton production at the NA62 experiment

Searches for heavy neutral lepton production in K+ --> e+N and K+ --> mu+N decays using the data set collected by the NA62 experiment at CERN in 2016-18 are presented. Upper limits on the elements of the extended neutrino mixing matrix $|U_{e4}|^2$ and $|U_{\mu4}|^2$ are established at the levels of $10^{-9}$ and $10^{-8}$, respectively, improving on the earlier searches for heavy neutral lepton production and decays in the kinematically accessible mass range. A search for the K+ --> mu+nuX decays, where X is an new light invisible particle, is also reported.

Speaker: Christopher John Parkinson (Universite catholique de Louvain)

Parkinson_NA62_HNL.pdf

T12: Detector R&D and Data Handling: Silicon and timing detectors

Conveners: Alessandro Cardini (INFN Sezione di Cagliari, Italy), Annika Vauth (Universität Hamburg)

291 The Phase-2 upgrade of the CMS Outer Tracker

The Large Hadron Collider at CERN will undergo a major upgrade in the Long Shutdown 2 from 2025-2027. The so-called High Luminosity LHC (HL-LHC) is expected to deliver peak instantaneous luminosities of about $5-7.5\times10^{34}$cm$^{-2}$s$^{-1}$ and an integrated luminosity of about $3000-4500\;$fb$^{-1}$ during ten years of operation. In order to fully exploit the delivered luminosity and to cope with the demanding operating conditions, the whole silicon tracking system of the CMS experiment will have to be replaced. The Phase-2 Outer Tracker (OT) will have an increased radiation hardness, a higher granularity, and will be able to cope with larger data rates. In addition, the OT will provide tracking information to the Level-1 trigger. To achieve this, each module will consist of two closely spaced sensors, which are connected to the same readout chips. The readout chips correlate data from both sensors for a rough transverse momentum measurement. This novel concept allows to keep trigger rates at a sustainable level without sacrificing physics potential. Furthermore, the Phase-2 OT will use evaporative CO$_{2}$ cooling and a DC-DC conversion based powering scheme to keep the material budget small. In this contribution, the design of the CMS Phase-2 Outer Tracker, highlights about research and development activities, and the present status of the project will be presented.

Speaker: Martin Lipinski

2021_07_27_ML_EPS.pdf

292 Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence of 1-5 10$^{15}$ 1 MeV n$_{eq}$/cm$^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance. A model of pixel digitization is presented that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to a thorough description of the setup, predictions are presented for basic pixel cluster properties alongside early studies with LHC Run 2 proton-proton collision data.

Speaker: Tomas Dado (TU Dortmund)

Dado_PixelRadDmg_EPS2021.pdf

293 CMS MTD Barrel Timing Layer: Precision Timing at the HL-LHC

The Compact Muon Solenoid (CMS) detector at the CERN Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the High-Luminosity LHC (HL-LHC). A new timing detector in CMS will measure minimum ionizing particles (MIPs) with a time resolution of 30-40 ps for MIP signals at a rate of 2.5 Mhit/s per channel at the beginning of HL-LHC operation. The precision time information from this MIP Timing Detector (MTD) will reduce the effects of the high levels of pileup expected at the HL-LHC, bringing new capabilities to the CMS detector. The barrel timing layer (BTL) of the MTD will use sensors that are based on LYSO:Ce scintillation crystals coupled to SiPMs with TOFHIR ASICs for the front-end readout. In this talk we will present motivations for precision timing at the HL-LHC and an overview of the MTD BTL design, including ongoing R&D studies targeting enhanced timing performance and radiation tolerance.

Speaker: Badder Marzocchi

EPS_BTL_MTD_Badder_Marzocchi_v2.pdf

294 A High-Granularity Timing Detector for the ATLAS Phase-II upgrade

The increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to L ~ 7.5 × 10$^{34}$ cm$^{-2}s^{-1}$ will have a severe impact on the ATLAS detector reconstruction and trigger performance.
The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer momentum resolution will be particularly affected. A High Granularity Timing Detector (HGTD) will be installed in front of the LAr end-cap calorimeters for pile-up mitigation and luminosity measurement.

The HGTD is a novel detector introduced to augment the new all-silicon Inner Tracker in the pseudo-rapidity range from 2.4 to 4.0, adding the capability to measure charged-particle trajectories in time as well as space.
Two silicon-sensor double-sided layers will provide precision timing information for minimum-ionising particles with a resolution as good as 30 ps per track in order to assign each particle to the correct vertex. Readout cells have a size of 1.3 mm × 1.3 mm, leading to a highly granular detector with 3.7 million channels. Low Gain Avalanche Detectors (LGAD) technology has been chosen as it provides enough gain to reach the large signal over noise ratio needed.

The requirements and overall specifications of the HGTD will be presented as well as the technical design and the project status. The on-going R&D effort carried out to study the sensors, the readout ASIC, and the other components, supported by laboratory and test beam results, will also be presented.

Speaker: Rachid Mazini (Academia Sinica (TW))

ATLAS_HGTD_mazini.pdf

295 Precision Timing with Low Gain Avalanche Detectors with the CMS Endcap Timing Layer for HL-LHC

The MIP Timing Detector (MTD) of the Compact Muon Solenoid (CMS) will provide precision timestamps with 40 ps resolution for all charged particles up to a pseudo-rapidity of |η|=3. This upgrade will mitigate the effects of pile-up expected under the High-Luminosity LHC running conditions and bring new and unique capabilities to the CMS detector. The endcap region of the MTD, called the Endcap Timing Layer (ETL), will be instrumented with silicon low gain avalanche detectors (LGADs), covering the high-radiation pseudo-rapidity region 1.6 < |η| < 3.0. The LGADs will be read out with the ETROC readout chip, which is being designed for precision timing measurements. We present recent progress in the characterization of LGAD sensors for the ETL and development of ETROC, including test beam and bench measurements.

Speaker: federico siviero (Università / INFN Torino)

Siviero_EPS2021_v2.pdf

296 Next and Present Generation of the Fast Silicon Timing Sensors for the LHC and the Next Generation of Future Colliders

The next generation of high energy physics colliders call for major advances in tracking detector technology. In order to cope with the increasingly demanding specifications of HEP experiments an extensive R&D program has been underway within the RD50 Collaboration to develop timing silicon sensors with sufficient radiation tolerance for HL-LHC trackers and beyond. The critical areas of detectors R&D include HV CMOS sensors, detectors made in the 3D technology and Low Gain Avalanche Detectors (LGADs). We will present the state of the R&D in several silicon detector domains, in particular, LGAD and 3D. We will also comment on the options for detector choices experiments beyond the LHC. Prospects of the fast-timing detectors for particle identification at the future Higgs factories and its implication on future frontier science will be discussed too.

Speaker: Gordana Lastovicka-Medin (University of Montenegro)

EPS-HEP_GLM.pptx

297 Tracking charged particles with O(10 ps) timing precision using 3D trench-type silicon pixels

One of the great challenges in the next generation of experiments at the future high-luminosity particle colliders will be the event reconstruction, as the large number of interactions occurring at each bunch crossing will create very large occupancies in the innermost detectors. In many of the studies performed for their upgrades, LHC experiments have showed that the addition of track timing measurements with an accuracy of the order of tens of picoseconds per track will restore tracking and vertexing capabilities at the levels we have today. In the last three years the TimeSPOT Collaboration has developed innovative silicon pixels allowing to reach a time resolution better than 20~ps on minimum ionizing particles. This new devices are 3D silicon pixels with trench electrodes, and they achieve such an outstanding time resolution thanks to both a highly uniform electric field inside the pixel and electrons/holes drift velocities close to saturation. Many different types of sensors, with pixel sizes ranging from 27.5 µm x 27.5 µm to 110 µm x 110 µm and arranged in matrices, multi-pixel strips or single-pixel test structures were produced in two batches in 2019 and 2020 by FBK in Trento, Italy. In a first beam test performed at the PSI πM1 beam-line in October 2019, time resolutions of about 20 ps per hit have been measured. In the last year accurate laboratory tests, both with a pulsed laser-based setup, able to precisely measure the sensor response throughout its active area, and with radioactive sources, emulating a test beam setup in the more controlled laboratory environment, have shown that these 3D pixel sensors intrinsically possess a time resolution close to 10 ps, and presently available front-end electronics represents a limit to their performances. The status of this developments and an outlook of future activities, will be presented at the Conference.

Speaker: Adriano Lai (INFN Sezione di Cagliari)

TimeSPOT10ps_ALai.pdf

298 Latest developments and characterisation results of the MALTA sensors in TowerJazz 180nm for High Luminosity LHC

The MALTA sensors are Depleted Monolithic Active Pixel Sensors (DMAPS) made using 180nm TowerJazz CMOS technology. These have been iteratively designed towards achieving a high radiation tolerance for applications such as in the outer layers of the HL-LHC’s ATLAS Inner Tracker. To date several design enhancements have been implemented to attain a high time resolution (<2ns), granularity as well as achieving excellent charge collection efficiency uniformly across the pixel geometries. This technology promises to drastically cut the production cost of silicon sensors due to their monolithic design, bypassing the costly stage of bump bonding in hybrid sensors. This talk will provide a detailed overview of the comprehensive characterisation studies conducted on the MALTA and Mini-MALTA sensors as well as present newer functionalities being introduced in the latest iteration, the MALTA2.

Speaker: Abhishek Sharma (CERN)

ASharma_EPS-HEP_2021.pdf

T13 - Accelerator for HEP: Part 1

299 Status and perspectives of the HL-LHC project

The HL-LHC project is in the process of transitioning from the R&D phase to the project production and implementation phase. The presentation presents updates from recent prototype tests of strategic accelerator equipment such as Nb3Sn magnets and crab cavities, reports on the progress of the civil engineering efforts currently ongoing at CERN and presents updates on the HL-LHC schedule and start-up plans.

Speaker: Oliver Bruning (CERN)

HEP-2021-V1.pptx

300 Status of the Electron Ion Collider

The Electron Ion collider will enable collisions of high energy ions with high energy electrons. It will shed light on many open questions of nuclear physics such as the origin of masses of nuclei and nucleons, the origin of nuclear spin, details on the distributions of constituents inside the nuclei, and the questions that emerge from the observed high density of gluons inside the nucleons. On December 19, 2019, the Department of Energy has granted Critical Decision-Zero (CD-0), the acknowledgement of Mission Need of the Electron Ion Collider proposal. On January 9, 2020, Brookhaven National Laboratory was chosen as the site of the new facility. Brookhaven National Laboratory  is forming a partnership with Thomas Jefferson Laboratory  to design, build and commission the new collider and its detector systems.
The EIC has very ambitious performance parameters that include high luminosity of up to 10^34 cm^-2s^-1, highly polarized beams with P<70%, large range of center of collision center of mass energies between 20 GeV and 140 GeV, large range of ion beams from protons to Uranium and the possibility of up to two detectors and interaction points.
Present plans call for start-up of collider operations in 2030. The design of the new collider is well advanced and recently passed successfully a series of thorough reviews of the conceptual design layout that is documented in a comprehensive conceptual design report.
Scientists from around the world are envisioned to use this exciting facility. There are expectations, that the worldwide science community will contribute to the detector and machine with in-kind contributions. This report will emphasize the status the verification of the design parameters and the accelerator design.

Speaker: Ferdinand Willeke

EIC_HEP_EPS_26Jul21-vs00 [Autosaved].pptx

301 Status and perspectives of the ILC and CLIC studies

A Higgs factory is considered the highest-priority next collider in the EPPSU 2020 strategy update. Two linear colliders projects, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC), currently under study are among the candidates being considered. Although the linacs accelerating the particles use different RF technologies they share similar challenges, for example related to nanobeams, injectors and positron production. The talk will summarize recent developments and the current status of the two projects, including their baselines parameters, on-going technology and performance studies, near future plans and international planning.

Speaker: Angeles Faus-Golfe (IJClab IN2P3-CNRS)

ILC-CLIC_EPS_AFG.pdf

302 Status and perspectives of the SuperKEKB project

The SuperKEKB electron-positron collider is being commissioned at KEK to study a new physics in the B-meson decays. In order to accomplish the target, the luminosity of 8 x 10$^{35}$ cm$^{-2}$s$^{-1}$ is necessary. We have applied a novel “nano-beam scheme” to squeeze the beta function at the interaction point (IP) down to 1 mm in the vertical, 60 mm in the HER and 80 mm in the LER in the horizontal direction, respectively. The beta function at the IP is the smallest value for the existing circular colliders in the world. However, the final design value is 0.3 mm which is about 1/3 of the achievement. Recently, we also applied a “crab waist collision scheme” to improve the luminosity in the nano-beam scheme. The status of the commissioning at 2020 run and 2021 run is presented and the performance of nano-beam scheme as well as the crab waist are discussed.

Speaker: Yukiyoshi Ohnishi (BELLE (BELLE II Experiment))

EPS-HEP2021_T13_4_SuperKEKB.pdf

303 Towards a Future Circular Higgs and Electroweak Factory

A large circular e+e- collider followed by a highest-energy hadron in the same tunnel promises the most far-reaching physics program for the post-LHC era, and such a facility could well serve the particle physics community through the end of the 21st century. Two such projects are presently proposed: The Future Circular Collider, in a global collaboration hosted by CERN, and the combination of Circular Electron Positron Collider and Super Proton-Proton Collider, advanced by IHEP Beijing. Over the centre-of-mass energy range from 90 to about 365 GeV, covering all known heavy elements of the Standard Model, from the Z resonance to the top-quark threshold, the circular e+e- collider offers a high luminosity and exquisite energy efficiency. The high luminosity is maintained by top-up injection from a full-energy booster synchrotron. On the Z pole and at the WW threshold resonant depolarisation will allow for a precision energy calibration at the ppm level. This presentation will summarize and compare the designs of FCC-ee and CEPC, covering the latest accelerator layouts and beam parameters, R&D plans, ongoing prototyping of key technologies, such as for the SRF system, and possible implementation schedules.

Speaker: Frank Zimmermann (CERN)

Towards a Future Circular Higgs and Electroweak Factory.pptx

304 Perspectives on novel neutrino beams

Neutrino beams today are delivered using technology first developed at CERN in the early 1960s. The next generation of long-baseline neutrino oscillation experiments, DUNE in the US, and Hyper-K in Japan, will exploit enormous detectors of exquisite sensitivity and resolution to deliver enormous data sets with which sensitive searches for the violation of the matter-antimatter symmetry can be made. The statistical weight of these experiments is such that beam-related systematic uncertainties are expexted to play a significant role. To drive the field beyond the sensitivity that will be delivered by DUNE and Hyper-K will require the development and exploitation of novel accelerator techniques. A number of techniques have been proposed to provide the well characterised neutrino beams required to take the field beyond the sensitivity of DUNE and Hyper-K. Such techniques include the creation of neutrino beams from the decay of stored muons and beams in which the neutrino flavour is tagged, and its energy is constrained, by instrumentation in the decay channel. The potential of such approaches will be reviewed and the status of the development of nuSTORM (Neutrinos from Stored Muons) ENUBET (Enanched Neutrino beam from Kaon Tagging) experiments, as well as other initiatives such as NuTAG and ESSnuSB), will be summarised. Synergies between the two programmes and with the R&D required to develop the muon-collider will be presented.

Speaker: Kenneth Long

2021-07-27-EPS-HEP-Long.pptx

11:30 Lunch Break

Plenary Session 1

Convener: Val Gibson

305 LHC Collider Status and Future

Speaker: Jörg Wenninger (CERN)

LHC-Status.EPS2021.pptx

recording

306 Highlights from the CMS Experiment

Speaker: Marco Pieri (UC San Diego)

MarcoPieriCMS_v1.1.pdf

recording

307 Highlights from the ATLAS Experiment

Speakers: Stephane Willocq (University of Massachusetts, Amherst), Stéphane Willocq (University of Massachusetts)

ATLAS-Highlights-2021-07-27-v4.pdf

recording

308 Standard Model Theory

Speaker: Jonas Lindert (University of Sussex)

JL_EPS2021.pdf

recording

14:30 Break

Review Stream 1: Session 1

Convener: Beate Heinemann (DESY and Freiburg University)

309 Higgs Measurements

Speaker: Kerstin Tackmann (BELLE (BELLE Gruppe))

EPS-Higgs.pdf

recording

310 Higgs Theory

Speaker: Veronica Sanz

EPSHEP.pdf

recording

Review Stream 2: Session 1

Convener: Federico Antinori

311 Emergence of Quark-Gluon Plasma Phenomena

Speaker: Francesca Bellini (University and INFN, Bologna, Italy)

20210727_Bellini_QGPemergence.pdf

recording

312 High-energy QCD Matter Theory

Speaker: Aleksas Mazeliauskas

mazeliauskas_EPS.pdf

recording

15:45 Break

T02: Cosmology: Part 1

Convener: Marko Simonovic (CERN)

313 Quality tests for the Heavy QCD axion

Heavy QCD axion models are motivated by the so-called "quality problem", the sensitivity of the QCD axion to misaligned contributions to its potential.
In this talk I will show that despite the absence of axion relics today, these models can generically produce a large amount of gravitational waves, a non-vanishing theta angle and, in some cases, both signals simultaneously.
Therefore, I will argue that GW observatories (e.g. LIGO-VIRGO-KAGRA, LISA) and future neutron and proton EDM experiments are good laboratories to search for the Heavy QCD axion.

Speaker: Ricardo Zambujal Ferreira (IFAE-Barcelona)

EPS-RicardoZFerreira.pdf

314 Cosmic Axion Background: the QCD axion as a hot relic

QCD Axions can be produced in various ways in the Early Universe by scatterings and decays from Standard Model particles, forming thus a Cosmic Axion Background that contributes to the abundance of relativistic relics (N_eff). We review in various setups how this is already constrained by present experiments and how it could be observed by future CMB experiments, in particular focusing on the coupling to quarks and leptons, the bounds on the DFSZ model, and also the connection with the Xenon1T excess.

Speaker: Alessio Notari

TalkEPS2021_np.pdf

315 Fragmentation of the axion field in the early universe

Axion-like-particle (ALP) is a well-motivated candidate for dark matter, and it has been subject to extensive theoretical and experimental research in recent years. The most popular ALP production mechanism studied in the literature is the misalignment mechanism, where the ALP field has negligible kinetic energy initially, and it starts oscillating when its mass becomes comparable to the Hubble scale. In most of these studies, the ALP field has been assumed to be a homogeneous classical field, and its quantum fluctuations have been ignored. However a non-zero initial velocity can cause exponential growth in the amplitude of fluctuations, and most of the energy density in the homogeneous mode can be converted to axion particles, known as fragmentation. In this talk I will present a semi-analytical study of this process, and describe the necessary ingredients for an efficient fragmentation. I will also mention some observational prospects such as the halo spectrum.

Speaker: Cem Eröncel (DESY)

eps-hep-2021.pdf

T04: Neutrino Physics: New interactions and neutrinos

Convener: Bjoern Soenke Wonsak (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik))

316 CP-Violating Neutrino Non-Standard Interactions in Long-Baseline-Accelerator Data

Neutrino oscillations in matter provide a unique probe of new physics. Leveraging the advent of neutrino appearance data from NOvA and T2K in recent years, we investigate the presence of CP-violating neutrino non-standard interactions in the oscillation data. We first show how to very simply approximate the expected NSI parameters to resolve differences between two long-baseline appearance experiments analytically. Then, by combining recent NOvA and T2K data, we find a tantalizing hint of CP-violating NSI preferring a new complex phase that is close to maximal: $\phi_{e\mu}$ or $\phi_{e\tau}\approx 3\pi/2$ with |$\epsilon_{e\mu}$| or |$\epsilon_{e\tau}$|$\sim$0.2. We then compare the results from long-baseline data to constraints from IceCube and COHERENT.

Speaker: Julia Gehrlein (Brookhaven National Laboratory)

eps_2021_gehrlein.pdf

317 Non-standard neutrino interactions in IceCube

Non-standard neutrino interactions (NSI) arise in various types of new physics. Their existence would change the potential that atmospheric neutrinos encounter when traversing Earth matter and hence alter their oscillation behavior. This imprint on coherent neutrino forward scattering can be probed using high-statistics neutrino experiments such as IceCube and its low-energy extension, DeepCore. Both provide extensive data samples that include all neutrino flavors, with oscillation baselines between tens of kilometers and the Earth diameter.
For DeepCore data samples, event energies reach from few GeV up to the order of 100 GeV - which marks the lower threshold for higher energy IceCube samples, ranging up to 10 TeV.
In DeepCore data the large sample size and energy range allow us to consider not only flavor-violating and -nonuniversal NSI in the $\mu-\tau$ sector, but also those involving the electron flavor.
The effective parameterization used in our analyses is independent of the underlying model and the new physics mass scale. In this way, competitive limits on several NSI parameters have been set in the past. The 8 years of data available now result in significantly improved sensitivities. This improvement stems not only from the increase in statistics but also from substantial improvement in the treatment of systematic uncertainties, background rejection and event reconstruction.

Speaker: Elisa Lohfink

elisa_lohfink_IceCube_NSI.pdf

318 Exploring Long-Range Force of $L_\mu-L_\tau$ Symmetry using Atmospheric Neutrino Experiment

Flavor-dependent long-range leptonic force mediated by an ultralight and neutral
gauge boson $Z'$ associated with $L_\mu -L_\tau$ symmetry constitutes a minimal
extension of the Standard Model. We study the physical consequences of such
long-range force in the oscillation of terrestrial neutrinos, particularly in $\nu_\mu$ survival channel. We show that the proposed atmospheric neutrino detector ICAL will be able to put tight constraints on such long-range force due to its capabilities of detecting neutrino and antineutrino separately with wide ranges of energies and baselines. The expected upper limit on the fine structure constant of this long-range force at $3\sigma$ is $2.82\times 10^{-51}$ using 500 kt$\cdot$yr exposure of ICAL. We also study the possible impact of the long-range force in the expected measurement of mass ordering at the ICAL in detail.

Speaker: Dr Amina Khatun (Comenius University, Bratislava)

EPS-AK-2.pdf

T05: Heavy Ion Physics: Part 5

Note: All contributions are given 12 minutes + 3 min for questions

319 Measurements of net-charge fluctuations across various colliding systems with ALICE

Event-by-event fluctuations of conserved quantities such as electric charge, baryon number and strangeness in ultrarelativistic heavy-ion collisions provide insight into the properties of the quark-gluon plasma and the QCD phase diagram. The net-charge fluctuations in finite phase space are usually studied using the $\nu_{dyn}$ observable, which is robust against the detection efficiency losses and with a proper multiplicity scaling it becomes equivalent to the strongly intensive quantity $\Sigma$. In this talk, the values of $\nu_{dyn}$ are explored with ALICE detector in various colliding systems, namely, pp and p-Pb at $\sqrt{s_{\rm NN}} = 5.02$ TeV, Pb-Pb at $\sqrt{s_{\rm NN}} = 2.76$ and 5.02 TeV, and Xe-Xe at $\sqrt{s_{\rm NN}} = 5.44$ TeV. The observed dependence of $\nu_{dyn}$ on charged-particle density shows a regular smooth evolution of net-charge fluctuations from smaller to larger collision systems. Furthermore, the observed negative values of $\nu_{dyn}$ indicate the dominance of correlation between the oppositely charged particle pairs as compared to those arising from the like-sign charge pairs. These findings are compared to the predictions of HIJING, EPOS and PYTHIA models. Effect of the kinematical acceptance has also been investigated by examining the $\nu_{dyn}$ dependence on the width of the pseudorapidity window within the ALICE acceptance $|\eta|<0.8$ and in different transverse momentum ranges, whereas the effect of the hadronic resonance decays is studied by comparing the experimental findings with the prediction of HIJING model.

Speaker: Shaista Khan

EPS2021_shaista.pdf

320 News from the NA61/SHINE strong-interactions program at CERN SPS

NA61/SHINE is a multipurpose fixed-target facility at the CERN Super Proton Synchrotron. The main goals of the NA61/SHINE strong-interactions program are to discover the critical point of strongly interacting matter as well as to study the properties of produced particles relevant for the study of the onset of deconfinement - the transition between the state of hadronic matter and the quark-gluon plasma., An analysis of hadron production properties is performed in nucleus-nucleus, proton-proton and proton-nucleus interactions as a function of collision energy and size of the colliding nuclei to achieve these goals.

In this presentation, the NA61/SHINE results from a strong interaction measurement program will be presented. In particular, the latest results from different reactions p+p, Be+Be, Ar+Sc, and Pb+Pb on hadron spectra and fluctuations are planned to be discussed. The NA61/SHINE results will be compared with results from worldwide experiments and with predictions of various theoretical models, like EPOS, PHSD, UrQMD and others. Finally, the motivation, NA61/SHINE plans of the measurements after LS2 and LS3 at the Super Proton Synchrotron energies will be shown.

Speaker: Szymon Pulawski (University of Silesia (PL))

EPS2021.pdf

321 System size and energy dependence of resonance production measured with ALICE

Hadronic resonances with different lifetimes are very useful to probe the hadronic phase, the latest stage in the evolution of the system created in heavy-ion collisions. Due to their relatively short lifetimes compared to the duration of the hadronic phase, resonances are good candidates to investigate the interplay between particle rescattering and regeneration. In addition, the measurement of resonances having different masses and strangeness content can contribute to the understanding of strangeness production. Measurements of hadronic resonances $\rho(770)^0$, K$^*(892)$, $\phi(1020)$, $\Sigma(1385)^\pm$, $\Lambda(1520)$, $\Xi(1530)^0$ and $\Xi(1820)$ have been performed with the ALICE detector at the LHC in pp, p–Pb, Pb–Pb and Xe–Xe collisions at different energies. We report on the transverse momentum ($p_{\rm T}$) spectra and $p_{\rm T}$ integrated yields, complementing our observation with new results on $\Lambda(1520)$ in p–Pb collisions at $\sqrt{s_{\rm NN}} =$ 8.16 TeV. In particular, ratios of $p_{\rm T}$-integrated resonance yields to those of long-lived particles will be discussed as a function of multiplicity in all collision systems at different energies. A critical overview of these results will be given through comparisons to measurements from other experiments and theoretical models.

Speaker: Paraskevi Ganoti

EPSHEP2021_Ganoti.pdf

T06: QCD and Hadronic Physics: Part 5: V + jets

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Mateusz Dyndal (AGH UST Krakow)

322 QCD physics measurements at the LHCb experiment

LHCb is a spectrometer that covers the forward region of proton-proton collisions, corresponding to the pseudo-rapidity range 2<eta<5. In this unique phase space, LHCb can perform tests of perturbative and non-perturbative QCD models, by studying the production of heavy flavor quarks, like charm and top quarks. In this context the production of a Z boson in association with a c-jet can be studied to measure the intrinsic charm content of the proton. Moreover LHCb can test phenomenological models of soft QCD processes, by measuring the production of forward hadrons in pp collisions.

Speaker: Lorenzo Sestini (INFN Padua and University of Padua)

qcd_lhcb_eps_v2.pdf

323 Application of parton showers obtained with the Parton Branching approach to Drell Yan + jets production

Calculations of Drell-Yan production at next-to-leading (NLO) order have been combined with transverse Momentum Dependent (TMD) distributions obtained with the Parton Branching (PB). For the first time, the predictions show a remarkable agreement with DY measurements across a wide range of DY mass and center of mass energies, from experiments like NuSea, R209, Phenix, CMS and ATLAS. Uncertainties from the TMD fit and from missing higher orders in the calculation are also determined. We also show predictions for Z+jet and multijet measurements, where especially angular correlations, sensitive to TMDs, are well described. We show that the PB TMDs together with a PB TMD parton shower and higher order matrix elements allow a very good description of measurements over a wide kinematic range.

Speaker: Armando Bermudez Martinez (CMS (CMS Fachgruppe QCD))

EPS2021.pdf

324 Vector boson associated with jets in CMS

The study of the associated production of vector bosons and jets constitutes an excellent enviroment to check numerous QCD predictions. Total and differential cross sections of vector bosons produced in association with jets have been studied in pp collisions using CMS data. Differential distributions as function of a broad range of kinematical observables are measured and compared with theoretical predictions.

Speaker: Qun Wang (DESY)

EPS_Vjet_QunWang.pdf

325 Measurement of prompt photon production and W/Z boson production in association with jets at ATLAS

The production of prompt isolated photons and W/Z-boson
in association with jets are an important test of perturbative QCD prediction and also yield information about the parton distribution functions of the proton.
In this talk, we present the latest measurements of prompt photon production using proton-proton collision data collected by the ATLAS experiment at √s=13 TeV. This includes the differential cross-section measurements of isolated di-photon production. We also present a measurement that probes the event topologies of prompt isolated photons produced in association with two hadronic jets. Latest results of differential cross-sections measurements for Z-boson production in association jets will be also presented including association with heavy flavour. Each measurement is corrected for detector inefficiency and resolution and the results are compared to state-of-the-art theory predictions, indicating several interesting discrepancies. If available, studies on the modelling of various processes in the state-of-art MC generators and fixed-order predictions will be presented.

Speaker: Heberth Torres (Dresden)

HTorres-EPS2021-ATLASPhotonAndZboson.pdf

326 Heavy flavored emissions in hybrid collinear/high energy factorization (12'+3')

Heavy-flavored emissions have been always considered as an excellent channel to test properties of Quantum chromodynamics (QCD) at present and future colliders. Among different regimes, in which heavy-flavor production can be investigated, we focus our attention on the semi-hard one, where $s>>Q^2>>\Lambda_{QCD}$ (s is the squared center-of-mass energy, $\{Q^2\}$ a (set of) hard scale(s) characteristic of the process and $\Lambda_{QCD}$ the QCD mass scale). Here, we build predictions in a hybrid collinear/high-energy factorization, in which the standard collinear description is supplemented by the Balitsky-Fadin-Kuraev-Lipatov resummation of large energy logarithms. The definition and the study of observables sensitive to high-energy dynamics in the context of heavy-flavor physics has the double advantage of (i) allowing to get a stabilization of the BFKL series under higher order corrections and (ii) providing us with an auxiliary tool to investigate heavy-flavor production in wider kinematical ranges. Hence, we propose a scientific program on heavy flavor physics at high energy that starts from the production of open states, with the ultimate goal of considering bound states (such as heavy-light mesons and quarkonia).
In this talk, after a brief overview on the theoretical set-up of high-energy factorization in the case of heavy-quark production, I will present some recent phenomenological analyses involving heavy-quark open states as well as bound states.

Speaker: Michael Fucilla (Università della Calabria)

EPSConference2021_Fucilla.pdf

T07-T09: Combined: Top, Electroweak and Higgs Physics: Part 1

Conveners: Eleni Vryonidou, Michael Trott (NBI)

327 Higgs boson production in association with top quarks with the ATLAS detector

The measurement of Higgs boson production in association with one or two top quarks is essential to understand the top-quark couplings to the Higgs boson. This talk presents the analyses using Higgs boson into several final states, using pp collision data collected at 13 TeV.

Speaker: Hongtao Yang (LBNL)

atlas_ttH_Hongtao_Yang.pdf

328 Probing the CP structure of the top quark Yukawa coupling: Loop sensitivity vs. on-shell sensitivity

The question whether the Higgs boson is connected to additional CP violation is one of the driving forces behind precision studies at the Large Hadron Collider. In this work, we investigate the CP structure of the top quark Yukawa interaction---one of the most prominent places for searching for New Physics---through Higgs boson loops in top quark pair production. We calculate the electroweak corrections including arbitrary CP mixtures at next-to-leading-order in the Standard Model Effective Field Theory. This approach of probing Higgs boson degrees of freedom relies on the large $t\bar{t}$ cross section and the excellent perturbative control. In addition, we consider all direct probes with on-shell Higgs boson production in association with a single top quark or top quark pair. This allows us to contrast loop sensitivity versus on-shell sensitivity in these fundamentally different process dynamics. We find that loop sensitivity in $t\bar{t}$ production and on-shell sensitivity in $t\bar{t}H$ and $tH$ provide complementary handles over a wide range of parameter space.

Speaker: Mr Ren-Qi Pan (Zhejiang University)

ttbar_EPS.pdf

329 Indirect CP probes of the Higgs–top-quark interaction: current LHC constraints and future opportunities

The CP structure of the Higgs boson in its coupling to the particles of the Standard Model is amongst the most important Higgs boson properties which have not yet been constrained with high precision. In this study, all relevant inclusive and differential Higgs boson measurements from the ATLAS and CMS experiments are used to constrain the CP-nature of the top-Yukawa interaction. The model dependence of the constraints is studied by successively allowing for new physics contributions to the couplings of the Higgs boson to massive vector bosons, to photons, and to gluons. In the most general case, we find that the current data still permits a significant CP-odd component in the top-Yukawa coupling. Furthermore, we explore the prospects to further constrain the CP properties of this coupling with future LHC data by determining tH production rates independently from possible accompanying variations of the tt̄H rate. This is achieved via a careful selection of discriminating observables. At the HL-LHC, we find that evidence for tH production at the Standard Model rate can be achieved in the Higgs to diphoton decay channel alone.

Speaker: Henning Bahl (T (Phenomenology))

EPS_Henning_Bahl.pdf

T10: Searches for New Physics: Part 5

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Cristina Botta (University of Zurich)

330 Search for new physics with long-lived and unconventional signatures in CMS

Many extensions of the standard model predict new particles with long lifetimes or other properties, that give rise to non-conventional signatures in the detector. This talk discusses new techniques to detect such signatures in the CMS detector, and presents recent results from such searches in CMS using the full Run-II data-set of the LHC.

Speaker: Bryan Cardwell

cardwell_llp_eps2021.pdf

331 Searches for BSM physics using challenging and long-lived signatures with the ATLAS detector

Various theories beyond the Standard Model predict unique signatures that are difficult to reconstruct and for which estimating the background rate is also a challenge. Signatures from displaced decays anywhere from the inner detector to the muon spectrometer, as well as those of new particles with fractional or multiple values of the charge of the electron or high mass stable charged particles are all examples of experimentally demanding signatures. The talk will focus on the most recent results using 13 TeV pp collision data collected by the ATLAS detector. Prospects for the HL-LHC will also be shown.

Speaker: Louie Corpe (CERN)

LCorpe_EPS2021_LLPsAndUnusualSignatures_ATLAS.pdf

332 Long-lived particles searches at LHCb

The unique design of the LHCb detector with a flexible trigger and a precision vertex tracker, offers the possibility to search for long-lived particles with low masses and short lifetimes, in complementarity with other general-purpose detectors at the LHC. Searches have been performed at LHCb, in fully leptonic and semi-leptonic final states. In particular, searches for long-lived particles produced in pairs from an exotic Higgs boson decay, and a search for heavy neutral leptons from a W boson decay, will be presented.

Speaker: Andrii Usachov

ausachov_EPS_21.pdf

333 Constraining electroweak and strongly charged long-lived particles with CheckMATE

Long-lived particles have become a new frontier in the exploration of physics beyond the Standard Model. In this paper, we present the implementation of four types of long-lived particle searches, viz. displaced leptons, disappearing track, displaced vertex (together with muons or with missing energy), and heavy charged tracks. These four categories cover the signatures of a large range of physics models. We illustrate their potential for exclusion and discuss their mutual overlaps in mass-lifetime space for two simple phenomenological models involving either a U(1)-charged or a coloured scalar.

Speaker: Nishita Desai (TIFR, Mumbai)

EPS-checkmate.pdf

334 Long-Lived Light Mediators from Higgs Decay at Hadron Colliders

In this work we study long-lived light mediators which are well-motivated for connecting the dark sector with standard model particles. Experiments like ATLAS and CMS have placed strong bounds on heavy mediators with prompt decay, however the landscape of light long-lived mediators needs attention. Current experimental constraints have pushed the allowed mixing with the SM Higgs boson for scalar, and the kinetic mixing for vector mediators to very small values, indicating long lifetimes. We focus on the pair production of the long-lived mediators from SM Higgs decay in this work. We study the combined projected sensitivity of general purpose detectors like CMS along with dedicated detectors for LLP searches like FASER, MATHUSLA, CODEX-b, in hadron colliders and the prospect of identifying the underlying LLP model and extracting its parameters using such a combination.

Speaker: Ms Rhitaja Sengupta (Indian Institute of Science, Bengaluru)

rhitaja_eps2021.pdf

T11: Quantum Field and String Theory: Part 1

335 Four-dimensional treatment of positivity bounds with gravity

We formulate Positivity Bounds for scattering amplitudes including exchange of gravitons in four dimensions. We generalize the standard construction through dispersion relations to include the presence of a branch cut along the real axis in the complex plane for the Maldestam variable s. In general, validity of these bounds require the cancellation of divergences in the forward limit of the amplitude. We show that this is possible only if one assumes a Regge behavior of the amplitude at high energies. As a non-trivial fact, a concrete UV behaviour of the amplitude is uniquely determined by the structure of IR divergences. We discuss also possible phenomenological applications of these bounds.

Speaker: Anna Tokareva (University of Jyvaskyla)

Positivity.pdf

336 Quantum breaking and scrambling: what 2 PI effective action can teach us

In this talk, after reviewing the concept of quantum breaking, and its relation to scrambling, concepts which proved fundamental for our understanding of composite systems such as condensates, black holes and De Sitter, I will show how to study them within the context of 2PI effective action. To do so I will focus on a simple model of a one dimensional condensate in which a logarithmic timescale emerges.

Speaker: Michael Zantedeschi (Max Planck Institute for Physik, Munich)

337 The string theory swampland in the Euclid, SKA and Vera Rubin observatory era

We explore the ability of future cosmological surveys to put constraints on string theory, through the Swampland program. String theory is sometimes thought to be unfalsifiable due to the incredibly large amount of low energy effective versions that can be derived in its framework. However, it is well known that constructing consistent solutions in a de-Sitter background is tremendously difficult. This led to speculative conditions on the possible shape of the potential of a dark energy scalar field. This postulate is referred to as the "de-Sitter conjecture" and low-energy effective theories that do not satisfy it are said to live in the Swampland. Future experiments, such as the Vera Rubin Observatory, Euclid or SKA, will set strong constraints on the form of dark energy and we investigated their potential conflict with the Swampland theoretical conditions. In particular, we show that the expected constraints on the equation of states of dark energy might be in strong contradiction with the de-Sitter conjecture and could therefore put string theory under pressure. Our study is carried out for many different quintessence potentials and a very wide range of initial conditions.

Speaker: Cyril Renevey (LPSC, Grenoble)

EPS.pdf

T12: Detector R&D and Data Handling: LHC Run2 operations and extrapolations

Conveners: Vincent Boudry (LLR – École polytechnique), Annika Vauth (Universität Hamburg)

338 Operational Experience and Performance with the ATLAS Pixel detector at the Large Hadron Collider at CERN

The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector. As the closest detector component to the interaction point, this detector is subjected to a significant amount of radiation over its lifetime. By the end of the LHC proton-proton collision RUN2 in 2018, the innermost layer IBL, consisting of planar and 3D pixel sensors, had received an integrated fluence of approximately Φ = 9 × 10$^{14}$ 1 MeV n$_{eq}$/cm$^2$.
The ATLAS collaboration is continually evaluating the impact of radiation on the Pixel Detector. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency will be described, with special emphasis to radiation damage experience. A quantitative analysis of charge collection, dE/dX, occupancy reduction with integrated luminosity, under-depletion effects with IBL, effects of annealing will be presented and discussed, as well as the operational issues and mitigation techniques adopted during the LHC Run2 and the ones foreseen for Run3.

Speaker: Tobias Bisanz (CERN)

EPS_talk_upload_conference.pdf

339 The Pixel Luminosity Telescope: a silicon sensor detector for luminosity measurement at CMS

The Pixel Luminosity Telescope is a silicon pixel detector dedicated to luminosity measurement at the CMS experiment. It consists of 48 silicon sensor planes arranged into 16 "telescopes" of three planes each, with eight telescopes arranged around the beam pipe at either end of the CMS detector, outside the pixel endcap at a distance of approximately 1.75 m from the interaction point. The planes in a telescope are positioned such that a particle coming from the interaction point passing through a telescope will produce a hit in each of the three planes of the telescope. The instantaneous luminosity is measured from this rate of triple coincidences, using a special "fast-or" readout at the full bunch-crossing rate of 40 MHz, allowing for real-time, high-precision luminosity information to be provided to CMS and the LHC. The full pixel information, including hit position and charge, is read out at a lower rate and can be used for studies of systematic effects in the measurement. We present the commissioning, calibration, operational history, and performance of the detector during Run 2 (2015-2018) of the LHC, together with lessons learned for future projects.

Speaker: Paul Lujan (University of Canterbury, New Zealand)

PixelLuminosityTelescope-EPS2021-final.pdf

340 Strategy for high-precision luminosity measurement with the CMS detector at the HL-LHC

The high-luminosity upgrade of the LHC (HL-LHC) is foreseen to reach an instantaneous luminosity a factor of five to seven times the nominal LHC design value. The resulting, unprecedented requirements for background monitoring and luminosity measurement create the need for new high-precision instrumentation at CMS, using radiation-hard detector technologies. This contribution presents the strategy for bunch-by-bunch online luminosity measurement based on various detector technologies. The potential of the exploitation of the tracker endcap pixel detector, the outer tracker, the hadron forward calorimeter, the barrel muon detectors and the 40 MHz scouting system is discussed together with the concept of a standalone luminosity and beam-induced background monitor using Si-pad sensors.

Speaker: Francesco Romeo (Vanderbilt University)

LumiHL_EPS21.pdf

341 Development of the ATLAS Liquid Argon Calorimeter Readout Electronics for the HL-LHC

To meet new TDAQ buffering requirements and withstand the high expected radiation doses at the high-luminosity LHC, the ATLAS Liquid Argon Calorimeter readout electronics will be upgraded. Developments of low-power preamplifiers and shapers to meet low noise and excellent linearity requirements are ongoing in 130nm CMOS technology. In order to digitize the analogue signals on two gains after shaping, a radiation-hard, low-power 40 MHz 14-bit ADCs is developed in 65 nm CMOS. The signals will be sent at 40 MHz to the off-detector electronics, where FPGAs connected through high-speed links will perform energy and time reconstruction through the application of corrections and digital filtering. The data-processing, control and timing functions will be realized by dedicated boards connected through ATCA crates. Results of tests of prototypes of front-end components will be presented, along with design studies on the performance of the off-detector readout system.

Speaker: Sana Ketabchi (Toronto)

ATLAS_LAr_HLLHC_EPS_vfinal.pdf

T14: Outreach, Education and Diversity: Part 1

342 Why people were on Facebook during your talk (And other lessons in effective communication for scientists)

Words can inspire, enlighten and motivate; but they can also confuse, frustrate and bore. In this short training, you’ll learn how to connect with your audience and explain ideas so that they’re not just understood, but have a meaningful impact. Skills covered are:

• Adapting communication goals and strategy to your target audience
• Talking with people who have no idea what you’re talking about
• Structuring information into a compelling (and memorable) story
• Staying sharp in high-stress situations

Speaker: Sarah Charley

EPS_communication_CHARLEY.pptx

343 How to Engage Public in Science Through Instagram

In this talk, you will discover how Instagram Stories are a powerful way to tell a story in a short and snappy way and engage the audience along the way. From developing science quizzes to engaging social media campaigns, you will learn the best practices of Instagram’s interactive features and make science more inclusive. Based on our experience at CERN, we will accelerate you on a journey to take science outreach in social media to another level.

Speaker: Chetna Krishna (CERN)

CERN Social Media at EPS-HEP .pdf

344 LGBTQ+ Inclusivity: How to be an ally

One of the key ingredients to do good science is the embrace of diversity in all its facets. The LGBTQ+ community faces extra burdens in our daily lives as scientists, making us less likely to stay in academia and achieve visible positions within large experiments.

The LGBTQ CERN group is a CERN-recognized Informal Network seeking to provide a welcoming space for lesbian, gay, bisexual, trans*, intersex, asexual, genderqueer and other LGBTQ+ individuals at CERN, also welcoming friends and allies. This talk will focus on the experiences of the LGBTQ CERN members in our careers in High Energy Physics, and discuss which concrete steps you can take, as an ally, to create a safe, inclusive and supportive scientific work environment.

Speaker: Mr Christos Vergis (Bonn University)

InclusivityAndDiversity_fin.pdf

Main Poster Session

This is the main poster session: all rooms are open, the posters can be watched, and the poster presenters are expected to 'stand' next to their posters. There will be full technical support.

Click here to access the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions).

Please also check the information how to enter and navigate the rooms on our main conference web page.

Access to the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions)

Wednesday, 28 July

T01: Astroparticle and Gravitational Waves: Part 5 (GW Theory)

Convener: Diego Blas (KCL)

345 Hyperbolic-like Encounters of Binary Black Holes

We present results on the encounter of two black holes that are initially on a hyperbolic-like orbit simulated with the numerical relativity code SpEC.
The two black holes either become bound due to the emission of gravitational waves or they escape to infinity. We present trajectories and waveforms for both cases and extract the scattering angle for the latter.

Speaker: Hannes Rüter (Albert Einstein Institute Potsdam)

2021-07-28 EPS Hyperbolic-like Encounters.pdf

346 Constraining Lorentz-violating gravity with gravitational wave observations

Models of Lorentz-violating gravity can provide a solution to the puzzle of quantum gravity. By abandoning boost invariance, we can formulate theories which are renormalizable and even asymptotically free in certain cases. At low energies, certain amount of Lorentz violation persists and can percolate onto physical observables, such as the emission rate of gravitational waves from a bounded system.

I will discuss how to constraint the parameter space of Einstein-Aether gravity and Hořava gravity with binary pulsar observations. This singles out a region of the parameter space which points towards a minimal model where only a single parameter remains non-vanishing. I will discuss how the theory then becomes indistinguishable from GR at many levels. Cosmological observables remain as the only possible source of deviations and the only hope to further constraining the theory.

Speaker: Mario Herrero Valea (SISSA)

LV-GW_pdf.pdf

347 Quantum black holes and ringdown physics with LIGO-Virgo detections

The gravitational-wave ringdown from black holes gives us direct access to the nature of space-time around them. Thus ringdown signals have the potential to shed some light on the quantum nature of black hole space-times. We present an observational investigation of the hypothesis that the black hole area is quantised in multiples of the Planck area. This hypothesis relies on a recently-proposed heuristic ringdown model built from the Bekenstein-Mukhanov area quantisation conjecture. We test this scenario by combining all the available information from the black hole population included in the GWTC-2 catalog. A time-domain analysis, based on the pyRing software used by the LVK Collaboration, is employed to quantify the evidence for the presence of signatures of the area quantisation in ringdown signals. We also discuss future prospects of effects due to the area quantisation with detections from ground-based detectors at their design sensitivity.

Speaker: Danny Laghi (University of Pisa and INFN PISA)

Danny_Laghi_HEP-EPS.pdf

348 GW190521 as a boson-star merger

In September 2020, Advanced LIGO-Virgo reported a short gravitational-wave signal (GW190521) interpreted as a quasi-circular merger of black holes, one at least populating the pair-instability supernova gap. In this talk I will show that GW190521 is consistent with numerically simulated signals from head-on collisions of two (equal mass and spin) horizonless vector boson stars (aka Proca stars) and provide estimate the mass of the corresponding ultralight vector boson. This provides the first demonstration of close degeneracy between these two theoretical models, for a real gravitational-wave event.

Speaker: Juan Calderon Bustillo (Galician Institute of High Energy Physics (IGFAE))

EPSHEP.pdf

349 Cosmology in the dark: How compact binaries formation impact the gravitational-waves cosmological measurements

Information about the mass spectrum of compact stars can be used to infer cosmological parameters from gravitational waves (GW) in the absence of redshift measurements obtained from electromagnetic (EM) observations. This method will be fundamental in measuring and testing cosmology with GWs for current and future ground-based GW detectors where the majority part of sources are detected without an associated EM counterpart.
In this talk, I will discuss the prospects and limitations of this approach for studying cosmology. I will show that, even when assuming GW detectors with current sensitivities, the determination of the Hubble constant is strongly degenerate with the maximum mass for black hole production.
I will discuss how assuming wrong models for the underlying population of black hole events can bias the Hubble constant estimate up to 40\%. I will then show how, when taking into account uncertainties on the population of black holes, it is possible to constrain the Hubble constant to a 10% accuracy and the maximum mass of black hole production to a value of 5% by combining 1000 GW event without and observed EM counterpart.

Speaker: Simone Mastrogiovanni (Astroparticule et Cosmologie Laboratoire, Universite de paris)

mastrogiovanni_EPS_amaldi_2021.pdf

350 Gravitational-wave signatures of non-integrable extreme-mass-ratio inspirals

The detection of gravitational waves from extreme-mass-ratio inspirals (EMRIs) with upcoming space-borne detectors will allow for unprecedented tests of general relativity in the strong-field regime. Aside from assessing whether black holes are unequivocally described by the Kerr metric, they may place constraints on the degree of spacetime symmetry. Depending on exactly how a hypothetical departure from the Kerr metric manifests, the Carter symmetry, which implies the integrability of the geodesic equations, may be broken.

In this talk, I will discuss the impact of non-integrability in EMRIs which involve a supermassive compact object with anomalous multipolar structure. After reviewing the particulars of chaotic phenomena in bumpy EMRIs, I will argue that non-integrability is precisely imprinted in the gravitational waveform. Explicit examples of non-integrable EMRIs will be discussed, as well as their role in LISA data analysis.

Speaker: Kyriakos Destounis (University of Tuebingen)

EMRIs_presentation_EPS-HEP2021.pdf

T02: Cosmology: Part 2

Convener: Camille Bonvin (University of Geneva)

351 Probing primordial features with the Stochastic Gravitational Wave Background

High energy embeddings of inflation often lead to departures from the single-field slow-roll paradigm, resulting in features in the primordial scalar power spectrum. Probing these features could, for instance, establish the existence of heavy particles beyond the reach of terrestrial experiments, and even test the inflationary paradigm or point to alternatives to it. To date, observational constraints and prospects for detection have concentrated on the CMB and Large Scale Structure surveys. 
In this talk, I will show how features in the primordial spectrum lead to characteristic oscillatory patterns in the stochastic gravitational wave background. This provides a clear target for gravitational wave observatories as well as a challenge for developing dedicated data analysis techniques to look for these unique insights into the physics of the early universe.

Speaker: Jacopo Fumagalli (IAP)

JFumagalli_EPS.pdf

352 A Multiple-Scales Approach to the Averaging Problem in Cosmology

The Universe is homogeneous and isotropic on large scales, so on those scales it is usually modelled as a Friedmann-Lemaître-Robertson-Walker (FLRW) space-time. The non-linearity of the Einstein field equations raises concern over averaging over small-scale deviations form homogeneity and isotropy, with possible implications on the applicability of the FLRW metric to the Universe, even on large scales. In this talk I will present a technique, based on the multiple-scales method of singular perturbation theory, to handle the small-scale inhomogeneities consistently. I will obtain a leading order effective Einstein equation for the large-scale space-time metric, which contains a back-reaction term. The derivation relies on a series of consistency conditions, that ensure that the growth of deviations from the large-scale space-time metric do not grow unboundedly; criteria for their satisfiability are discussed, and it is shown that they are indeed satisfied if matter is non-relativistic on small scales. The analysis is performed in harmonic gauge, and conversion to other gauges is discussed. I will also estimate the magnitude of the back-reaction term relative to the critical density of the Universe in the example of an NFW halo. In this example, the back-reaction term can be interpreted as a contribution of the energy-density of gravitational potential energy, averaged over the small-scale, to the total energy-momentum tensor.

Speaker: Barry Ginat (Technion - Israel Institute of Technology)

ginat_eps_hep21.pdf

353 Early galaxy formation and its implications for 21cm cosmology, dark matter and multi-messenger astronomy

Galaxy formation in the first billion years mark a time of great upheaval in the history of the Universe: as the first sources of light, these galaxies ended the 'cosmic dark ages' and produced the first photons that could break apart the hydrogen atoms suffusing all of space starting the process of cosmic reionization. As the earliest building blocks, the galaxies that formed in the first billion years also determine the physical properties of all subsequent galaxy populations. I will start by introducing the reionization process and detail the reasons for which the history and topology of reionization remain debated. I will then show how cross-correlations of 21cm data with the underlying galaxy population, in the forthcoming era of 21cm cosmology, will yield tantalising constraints on the average intergalactic medium ionization state as well as the reionization toplogy (outside-in versus inside-out). I will try to give a flavour of how the assembly of early galaxies, accessible with the forthcoming James Webb Space Telescope, can provide a powerful testbed for Dark Matter models beyond "Cold Dark Matter". Finally, I will show the importance of black hole seeding and baryonic feedback in determinging the LISA detectability of merger events from the early universe.

Speaker: Pratika Dayal (Kapteyn Astronomical institute, university of groningen)

Dayal_eps_cosmology.pdf

354 Entropy in the early universe

Due to the quantum origin of primordial perturbations, the early universe is an ideal setup for the interplay between gravity, quantum physics and thermodynamics. In this talk I will discuss results and ongoing work on the role that mutual information between distant regions play in cosmology.

Speaker: Llorenç Espinosa-Portalés (Instituto de Física Teórica UAM-CSIC)

2021_EPS-HEP_LEP.pdf

355 Self-interacting neutrinos as a solution(?) to the Hubble tension

Self-interaction among the neutrinos in the early Universe has been proposed as a solution to the Hubble tension, a discrepancy between the measured values of the Hubble constant from CMB and low-redshift data. However, flavor-universal neutrino self-interaction is highly constrained by BBN and several laboratory experiments such as, tau and K-meson decay, double-neutrino beta decay etc. In this talk, I will discuss about the cosmology if only one or two neutrino states are self-interacting. Such flavor-specific interactions are less constrained by the laboratory experiments. Finally, I will talk about the feasibility of addressing the Hubble tension in the framework of such flavor-specific neutrino self-interaction.

Speaker: Anirban Das (SLAC National Accelerator Laboratory)

SInu-Hubble short.pdf

356 Reconstruction of the neutrino mass as a function of redshift

In this talk, we present a reconstruction of the neutrino mass as a function of redshift, $z$, from current cosmological data using both standard binned priors and linear spline priors with variable knots. Using Planck 2018 cosmic microwave background temperature, polarization and lensing data, in combination with distance measurements from baryonic acoustic oscillations and supernovae, we find that the neutrino mass is consistent with $\sum m_\nu(z)=$ const. We obtain a larger bound on the neutrino mass at low redshifts coinciding with the onset of dark energy domination, $\sum m_\nu(z=0)<1.46$ eV (95% CL). We comment on how this result can be explained either by the well-known degeneracy between $\sum m_\nu$ and $\Omega_\Lambda$ at low redshifts, or by models in which neutrino masses are generated very late in the Universe. We finally convert our results into cosmological limits for models with post-recombination neutrino decay and comment on neutrino mass detection prospects with the KATRIN experiment.

Speaker: Lena Funcke (Perimeter Institute)

EPS-HEP2021-Funcke.pdf

T03: Dark Matter: Part 5

Convener: Kallia Petraki (LPTHE, Sorbonne)

357 DRAKE: Dark matter Relic Abundance beyond Kinetic Equilibrium

In the usual approach to the determination of the dark matter thermal relic abundance an assumption of local thermal equilibrium is made. In this talk I will discuss how to go beyond this assumption and introduce DRAKE — a numerical precision tool that can trace not only the DM relic density, but also its velocity dispersion and full phase space distribution function. I will review the general motivation for this approach and, for illustration, highlight three concrete classes of models where kinetic and chemical decoupling are intertwined in a way that can impact the value of the relic density by as much as an order of magnitude: i) dark matter annihilation via a narrow resonance, ii) Sommerfeld-enhanced annihilation and iii) `forbidden' annihilation to final states that are kinematically inaccessible at threshold.

Speaker: Andrzej Hryczuk (National Centre for Nuclear Research, Poland)

EPS2021_Hryczuk.pdf

358 Cosmological imprints of non-thermalized dark matter

Non-thermalized dark matter is a cosmologically valid alternative to the paradigm of weakly interacting massive particles. For dark matter belonging to a $Z_2$-odd sector that also contains a thermalized mediator particle, dark-matter production proceeds via both the freeze-in and super-WIMP mechanism. We highlight their interplay and study the evolution of the resulting dark-matter phase-space distributions in detail. Utilizing our implementation into CLASS, we investigate their cosmological imprints on the matter power spectrum, constrained, in particular, by Lyman-alpha forest observations. For the explicit example of a colored t-channel mediator model, we map out the entire cosmologically viable parameter space, cornered by bounds from the LHC, big bang nucleosynthesis, and the matter power spectrum on small scales.

Speaker: Jan Heisig (Université catholique de Louvain (UCL))

Heisig_EPS2021_sWmFI.pdf

359 Dissecting the inner Galaxy with gamma-ray pixel count statistics

The nature of the GeV gamma-ray Galactic center excess (GCE) in the data of Fermi-LAT is still under investigation. Different techniques, such as template fitting and photon-count statistical methods, have been applied in the past few years in order to disentangle between a GCE coming from sub-threshold point sources or rather from diffuse emissions, such as the dark matter annihilation in the Galactic halo.
A major limit to all these studies is the modeling of the Galactic diffuse foreground, and the impact of residual mis-modeled emission on the results' robustness.
In Ref.[1], we combine for the first time adaptive template fitting and pixel count statistical methods in order to assess the role of sub-threshold point sources to the GCE, while minimizing the mis-modelling of diffuse emission components.
We reconstruct the flux distribution of point sources in the inner Galaxy well below the Fermi-LAT detection threshold, and measure their radial and longitudinal profiles. We find that point sources and diffuse emission from the Galactic bulge each contributes about 10% of the total emission therein, disclosing a sub-threshold point-source contribution to the GCE.

[1] arXiv:2102.12497

Speaker: Francesca Calore (CNRS, LAPTh)

EPS-HEP21_FCalore.pdf

360 Circular polarisation of gamma rays as a probe of dark matter-cosmic ray electron interactions

Dark Matter (DM) constitutes most of the matter in the presently accepted cosmological model for our Universe. However, despite the increased sensitivity of direct and indirect DM searches, and the latest LHC run at 13 TeV centre of mass energy, no signal from DM particles has been detected so far, leading to exclusion limits on the parameter space of DM models. Conventional indirect searches look for an excess in the electromagnetic emission from the sky that cannot be attributed to known astrophysical sources, but polarisation is so far not being explored.

In this talk, I will argue that the photon polarisation is an important feature to understand new physics interactions. In particular, circular polarisation can be generated from Beyond the Standard Model (BSM) interactions if they violate parity and there is an asymmetry in the number of particles which participate in the interaction. I will consider a simplified model for fermionic (Majorana) DM and study the circularly polarised gamma rays below 10 GeV from DM cosmic ray electron interactions. I will study the differential flux of positive and negative polarised photons from the Galactic Centre and show that the degree of circular polarization can reach up to 90%. Finally, I will discuss the detection prospects of this signal in future experiments.

Speaker: Marina Cermeño Gavilán (UCLouvain (CP3))

Cermeno_EPS_talk.pdf

361 Indirect Dark Matter Searches with the ANTARES and KM3NeT Neutrino Telescopes

Neutrino telescopes perform an indirect search for dark matter (DM) through its annihilation into standard model channels yielding neutrinos, for a broad range of WIMP masses. The ANTARES telescope, anchored to the Mediterranean seabed at a depth of about 2500 m, looks for a DM signal from two promising sources with high WIMP density: the Galactic Center and the Sun. We present the latest results of ANTARES on indirect detection for several WIMP masses and channels, and give a future prospect on sensitivities of DM searches with KM3NeT, the next-generation neutrino telescope, currently in deployment in the Mediterranean Sea. These detectors have specific advantages, complementary to other strategies, and can provide a smoking-gun signal in the case of the Sun. The geographical location of ANTARES and KM3NeT is particularly suited for searches in the Galactic Center, allowing for the world-best limits on annihilation cross-section for large WIMP masses.

Speaker: Daniel Lopez-Coto (ANTARES/KM3NeT)

DM_ANTARES_KM3NeT-EPS-HEP.pdf

362 Dark Matter Searches with the IceCube Neutrino Telescope

The existence of dark matter (DM) has been well-established by repeated experiments probing various length scales. Even though DM is expected to make up 85% of the current matter content of the Universe, its nature remains unknown. Numerous methods have been developed to search for DM—both directly by looking for excess energy created in DM interaction with normal matter and indirectly by looking or DM's effect on normal matter. The IceCube Neutrino Observatory—a cubic-kilometer of instrumented ice located beneath the geographic South Pole, which detects Cherenkov radiation of charged particles produced in neutrino interactions—is well-suited to the latter class of searches. Depending on the nature of DM, IceCube may observe, among other signatures, an excess of neutrinos, a modified directional distribution, or a modified flavor distribution. In this contribution, I will highlight IceCube's recent indirect DM searches and their results.

Speaker: Jeffrey Lazar (UW-Madison)

jlazar_eps_20210728v2.pdf

T04: Neutrino Physics: HNL/LNV

Convener: Pilar Coloma (Instituto de Fisica Teorica UAM/CSIC)

363 Recent astroparticle and exotic physics results from MicroBooNE

MicroBooNE is an 85-ton active mass liquid argon time projection chamber (LArTPC) at Fermilab. Its excellent calorimetry and resolution, along with its exposure to two neutrino beam lines (BNB and NuMI) make it a powerful detector not just for neutrino physics, but also for Beyond the Standard Model (BSM) physics and astroparticle physics. The experiment has competitive sensitivity to heavy neutral leptons arising in the leptonic decay modes of kaons, and also to scalar bosons that can be produced in kaon decays in association with pions. In addition, MicroBooNE serves as a platform for prototyping searches for rare events in the future Deep Underground Neutrino Experiment (DUNE). This talk will explore the capabilities of LArTPCs for BSM physics and astrophysics and highlight some recent results from MicroBooNE.

Speaker: Pawel Guzowski (The University of Manchester)

epshep.pdf

364 Measuring TeV neutrinos with FASERnu in the LHC Run-3

The FASER$\nu$ detector at the LHC has been designed to study neutrinos at the highest man-made energies. The detector will be located 480 m downstream of the ATLAS interaction point, and will take data starting in 2022. With FASER$\nu$, the three-flavor neutrino cross-sections will be measured in the currently unexplored energy range between 360 GeV and 5 TeV. In particular, tau-neutrino and electron-neutrino cross sections will be measured at the highest energy ever.

In 2018 we performed a pilot run with the aims of measuring particle fluxes at the proposed detector location and of possibly detecting neutrino interactions for the first time at the LHC. We installed a 30-kg lead/tungsten emulsion detector and collected data of 12.2 fb$^{-1}$. The analysis of this data has yielded several neutrino interaction candidates, excluding the no-signal hypothesis at the 2$\sigma$ level. We have also studied the charged particle flux (mainly muons) in regard to the characterization of the unprecedented collider neutrino beamline.

During Run-3 of the LHC starting from 2022, we will deploy an emulsion detector with a target mass of 1.1 tons, coupled with the FASER magnetic spectrometer. This would yield roughly 1,300 $\nu_e$, 9,000 $\nu_{\mu}$, and 30 $\nu_{\tau}$ interacting in the detector. Here we present the status and plan of FASER$\nu$, as well as the neutrino detection in the 2018 data.

Speaker: Tomoko Ariga (Kyushu University (JP))

20210728_tariga_FASERnu_EPS_v2.pdf

365 Testing the neutrino mass generation mechanism at the future colliders

The generation of the neutrino mass is an essential observation from the neutrino oscillation experiments. This indicates a major revision of the Standard Model which initiated with the massless neutrinos. A possible interesting scenario is the seesaw mechanism where SM gauge singlet Right Handed Neutrinos are introduced. Another interesting aspect is the extension of the SM with $SU(2)_L$ triplet fermions. Alternatively a general $U(1)$ extension of the SM is also an interesting idea which involves three generations of the SM singlet RHNs to generate the tiny neutrino mass through the seesaw mechanism. Additionally such models can contain a $Z^\prime$ boson which could be tested at the colliders through the pair production of the RHNs.

Speaker: Arindam Das (Osaka U)

ADas_EPS2021.pdf

366 Constraining lepton number violating interactions with rare meson decay

The possibility of new physics in terms of lepton number violating (LNV) interactions is intriguing out of various reasons: LNV could be tightly linked to the generation of neutrino masses of Majorana nature while at the same time having direct implications for the generation of the baryon asymmetry of our Universe. The $K \rightarrow \pi \nu \bar{\nu}$ decay is one of the most promising modes to search for physics beyond the Standard Model and is able to probe mass scales higher than other rare meson decays. Motivated by the goal of the NA62 experiment to reach SM precision in $K \rightarrow \pi \nu \bar{\nu}$, I will consider the implications of a potential deviation from the SM expectation and estimate the new physics scale associated with potential LNV effects. Finally, I will discuss the potential to discern the Majorana or Dirac nature of neutrinos in rare meson decays.

Speaker: Julia Harz (Technical University of Munich (TUM))

EPS2021.pdf

367 Z-Boson Decays into (Heavy) Neutrinos: Dirac or Majorana?

Recently Z factories have been proposed with the capability to produce more than 10^12 Z bosons. It has been observed that this opens the possibility to observe the decay of the Z into a light neutrino and a heavy neutrino, Z --> vN, down to very small (10^{-11}) light-heavy neutrino mixing angles and up to masses close to the Z mass. The question of whether the heavy neutrino is a Dirac particle (conserving lepton number) or a Majorana particle (leading to violation of lepton number conservation) is raised and analyzed, with the following conclusion: in spite of the fact that it is not possible to distinguish the two hypotheses on an event by event basis, it is possible to build two observables, the charge asymmetry and the polarization analysis, which, given sufficient statistics, would allow a significant determination of the nature of the heavy neutrino.

Speaker: Prof. Andre de Gouvea

EPS_HEP_2021.pdf

368 The DUNE Near Detector Complex as a Beam Dump Facility

Two of the greatest mysteries that particle physics faces today are the fact that neutrinos have mass and the existence of dark matter. Upcoming experiments are on the horizon attempting to unveil more about both of these, but there is the possibility that we can learn about both in one environment. The Deep Underground Neutrino Experiment, a next-generation experiment planned for the US in the late 2020s and beyond, will have a suite of near detectors designed to better understand neutrino fluxes and interactions, however, it has capabilities for discovering beyond-the-Standard-Model physics as well. In this talk, I will demonstrate how this complex can be seen as a sort-of “Beam Dump” facility, enabling searches for new particles, such as heavy neutrinos, dark Higgs bosons, and axion-like particles.

Speaker: Kevin Kelly (Fermilab)

KJK_EPSHEP_2021.pdf

T06: QCD and Hadronic Physics: Part 6: Soft physics

Note: All contributions are given 12 minutes + 3 min for questions

Conveners: Prof. laura Fabbietti (TUM), Ferenc Siklér (Wigner RCP, Budapest)

369 Measurement of charged particle multiplicity distributions in DIS at HERA and its implication to entanglement entropy of partons

Charged particle multiplicity distributions in positron-proton deep inelastic scattering at a centre-of-mass energy $\sqrt{s}=319$ GeV are measured. The data are collected with the H1 detector at HERA corresponding to an integrated luminosity of $136$ pb$^{-1}$. Charged particle multiplicities are measured as a function of photon virtuality $Q^2$, inelasticity $y$ and pseudorapidity $\eta$ in the laboratory and the hadronic centre-of-mass frames. Predictions from different Monte Carlo models are compared to the data. The first and second moments of the multiplicity distributions are determined and the KNO scaling behaviour is investigated. The multiplicity distributions as a function of $Q^2$ and the Bjorken variable $x_{\rm Bj}$ are converted to the hadron entropy $S_{\rm hadron}$, and predictions from a quantum entanglement model are tested.

Eur.Phys.J.C 81 (2021), 212

Speaker: Zhoudunming Tu (BNL)

slides_Tu.pdf

370 Extending the ALICE strong-interaction studies to nuclei: measurement of proton-deuteron correlations in pp collisions at $\sqrt{s} = 13$ TeV

The large data sample of high-multiplicity pp collisions collected by ALICE allows for the precise measurement of the size of the source producing primary hadrons, opening the door to the study of the interaction of different hadron species using femtoscopy techniques. The momentum correlation between (anti)protons and (anti)deuterons measured in pp collisions at $\sqrt{s}=$ 13 TeV with ALICE is studied here for the first time. The measured correlation function for ($\bar{\rm p}$)${\rm p}$–($\bar{\rm d}$)${\rm d}$ pairs is compared with theoretical predictions based on both Coulomb interaction only and Coulomb plus strong interactions, employing the Lednický-Lyuboshitz model and the scattering parameters extracted from p-d scattering experiments. In both cases, the measured correlation function cannot be reproduced by the predictions. This deviation is interpreted as a demonstration of the late formation time of (anti)deuterons in hadron-hadron collisions. This observation is key for the understanding of the production mechanism of light (anti)nuclei, which is an open issue in high-energy physics and has also important consequences for the study of antinuclei formation in the interstellar medium either from collisions triggered by high-energy cosmic rays or by dark matter decays.

Speaker: Bhawani Singh

EPS2021_Bhawani.pdf

371 Production of light nuclei in small collision systems measured with ALICE

The energy densities reached in high-energy hadronic collisions at the LHC allow significant production of light (anti)nuclei. Their production yields have been measured as a function of $p_{\mathrm{T}}$ and charged-particle multiplicity in different collision systems and at different center-of-mass energies by ALICE. One of the most interesting results obtained from such a large variety of experimental data is that the dominant production mechanism of light (anti)nuclei seems to depend solely on the event charged-particle multiplicity. Evidence for this comes from the continuous evolution of the deuteron-to-proton and $^{3}$He-to-proton ratios with the event multiplicity across different collision systems and energies. The characterization of the light nuclei production mechanism is complemented by measurements of their production yields in jets, where hard QCD processes are dominant, and in the underlying event, which is dominated by soft QCD processes.

In this contribution, recent results on the measurements of light-nuclei production in proton-proton and proton-lead collisions at different center-of-mass energies are shown and discussed in the context of the statistical hadronization and coalescence models. In addition, final results on the deuteron production in jets and new preliminary results on its production in the underlying event measured in proton-proton collisions at 13 TeV are shown.

Speaker: Alessandro Balbino (Politecnico and INFN di Torino (IT))

nuclei_smallsystems_EPS2021.pdf

372 Light flavor particle production across different systems and energies with ALICE

The study of the production of particles of different masses as a function of event multiplicity is a key tool for understanding the soft QCD processes and hadronization. In this talk, we report ALICE results on transverse momentum spectra and yields of $\pi$, K, p, $K^{0}_{S}$, $\Lambda$, $\Xi$ and $\Omega$ measured in pp, p-A, and A-A collisions, including the recently published results in Pb-Pb and Xe-Xe collisions at $\sqrt{s_{\rm NN}} = 5.02$ and $5.44$ TeV, respectively. Particle spectra and ratios as measured in pp and A-A collisions are compared at similar charged-particle multiplicity densities ($\langle{\rm d}N_{\rm ch}/{\rm d}\eta\rangle$), and, for A-A collisions, at different initial eccentricities. Results on the hadron abundances measured in high-multiplicity pp collisions at $\sqrt{s}=13$ TeV as a function of event shape will be shown. In addition, to better understand the contribution of the event multiplicity to the observed enhancement of strange particles in pp, two new complementary analyses have been performed. The first classifies events according to the anti-correlation between mid-rapidity multiplicity and the energy deposited in the ALICE Zero Degree Calorimeters. The second exploits the angular correlation between strange and high-$p_{\rm T}$ charged hadrons to distinguish in-jet and out-of-jet strangeness production. Results indicate that strangeness enhancement correlates with the growth of the underlying event, which can be selected by employing a forward-rapidity classifier. Finally, results are discussed in the context of statistical hadronization models as well as pQCD-inspired models.

Speaker: Michael Habib

EPS21_mh.pdf

373 Particle production at midrapidity in correlation with the very forward energy in pp and p-Pb collisions with ALICE ZDC

The very forward energy detected by the ALICE Zero Degree Calorimeters (ZDC) measures the beam remnants, whose energy decreases as the activity at midrapidity increases. A pseudorapidity gap of nearly 9 units between the ZDC ensures that any correlation between the very forward energy and the midrapidity production originates in the initial scatterings. The measurement of these correlations, done for the first time at LHC energies, provides direct insights into particle production and the initial stages of the collisions. The energy detected in the zero-degree hadronic calorimeters in pp collisions at $\sqrt{s}$ = 13 TeV and in p-Pb collisions at $\sqrt{s_{NN}}$ = 8.16 TeV will be presented and compared with the expectations of several hadronic interaction models. Underlying event (UE) measurements give insight into models implementing impact-parameter dependent multiparton interaction (MPI) production. The novel measurement of the relation between very forward energy and production of large transverse momentum particles at midrapidity provides complementary information to UE analysis.

Speaker: Chiara Oppedisano

EPS21-COppedisano.pdf

374 Charged hadron production at LHCb

With a unique geometry covering the forward rapidity region, the LHCb detector provides unprecedented kinematic coverage at low x for charged particles in hadron collisions. The excellent momentum resolution, vertex reconstruction, and particle identification allows precision measurements down to very low pT. This talk will present recent LHCb measurements of prompt charged hadron production in proton-proton and proton-lead collisions. Comparisons with various event generators and nPDF calculations are discussed.

Speaker: Óscar Boente García (Instituto Galego de Física de Altas Enerxías - USC)

EPSHEP2021_oboente.pdf

375 LHCb Fixed-target results and prospects

Originally conceived for precise luminosity measurements, the gas injection system SMOG currently allows the unique LHCb detector capabilities to be exploited for fixed-target studies in proton-gas collisions at sqrt(s) ~ 100 GeV. The first results obtained with SMOG data are reported: antiproton production with a He target and J/psi , D0 productions in pHe and pAr collisions. The upgraded system SMOG2, which will be used during Run 3 of LHC, will extend the target species available and increase the areal gas density, offering a unique opportunity for measurements related to hadron production, cosmic rays physic and nucleon structure at the LHC. An overview of the SMOG2 system and its prospects is reported along with a selection of interesting physical measurements.

Speaker: Saverio Mariani

Mariani_EPS2021_FixedTarget.pdf

376 χ_c and χ_b meson produciton in high multiplicity events

Recently studies of the heavy J/ψ and D-mesons by ALICE and STAR collaborations revealed a pronounced dependence of the cross-section on multiplicity of co-produced charged particles, and one of the possible explanations of this phenomenon is the enhanced contribution of multipomeron configurations. In this talk we present our theoretical results for the production of P-wave quarkonia (χ_c and χ_b mesons) in proton-proton collisions. We expect that, due to different quantum numbers, the χ_c and χ_b meson production cross-section does not get contributions from 3-pomeron fusion, and for this reason the multiplicity dependence of the cross-section should be significantly milder than that of J/ψ and D-mesons. We expect that the experimental confirmation of this result could constitute an important test of our understanding of multiplicity enhancement mechanisms in the production of different quarkonia states. We also present detailed production cross-sections in kinematics of ongoing experiments at LHC and RHIC.

This presentation is partially based on our recent publication [Eur.Phys.J.C 80 (2020) 6, 560] and arXiv submission https://arxiv.org/abs/2012.08284

Speaker: Dr Marat Siddikov (Federico Santa Maria Technical University (UTFSM))

Talk_EPSHEP2021_Chi_cb3.pdf

T07-T09: Combined: Top, Electroweak and Higgs Physics: Part 2

Conveners: Alexander Grohsjean (CMS (CMS Fachgruppe TOP)), Michael Trott (NBI)

377 Precision from Diboson Processes at FCC-hh

Thanks to its high luminosity and center of mass energy, the future FCC-hh collider will allow us to probe processes with clean but rare final states that are unaccessible at the LHC. The study of diboson production processes poses a promising way of indirectly constraining New Physics in the context of the Higgs Boson. Specifically, the diphoton leptonic decay channels of the Wh and Zh production processes are examples for the aforementioned clean but rare final states. I will discuss our study of these channels at the FCC-hh in the SMEFT framework and how doubly differential distributions can be used to gain even better sensitivity to certain higher dimensional EFT operators.

Speaker: Philipp Englert (T (Phenomenology))

Slides_Englert_EPS2021.pdf

378 Parton Distributions in the SMEFT from high-energy Drell-Yan tails

The high-energy tails of charged- and neutral-current Drell-Yan (DY) processes provide important constraints on the light quark and anti-quark parton distribution functions (PDFs) in the large-x region. On the other hand, a hypothetical short-distance new physics would smoothly distort the high-energy tails as described by the Standard Model Effective Field Theory (SMEFT). In this work, we assess for the first time the interplay between PDF and EFT effects in the high-mass Drell-Yan at the LHC. We determine to which extent EFT signals that would manifest themselves in the tails of the Drell-Yan distributions could be reabsorbed into the large-x (anti-)quark PDFs, and present a strategy aimed at disentangling possible New Physics effects from proton structure modifications. We quantify the impact that a consistent joint determination of the PDFs and Wilson coefficients has in two motivated short-distance new physics scenarios: 1) electroweak oblique corrections and 2) four-fermion interactions possibly behind the LHCb anomalies in R(K(∗)). Finally, we present dedicated projections for the High-Luminosity LHC and evaluate its ultimate potential to constrain the EFT parameters, while taking into account potential modifications of the proton structure.

Speaker: Ms Maeve Madigan (University of Cambridge)

Madigan_EPSHEP2021.pdf

379 Heavy states and electroweak effective approaches

The existence of a mass gap between the Standard Model (SM) and possible new states encourages us to use effective field theories. Here we consider the non-linear realization of the electroweak symmetry breaking: the electroweak effective theory (EWET), also known as Higgs effective field theory (HEFT) or electroweak chiral Lagrangian (EWChL). At short distances a resonance Lagrangian which couples the SM states to bosonic and fermionic resonances is assumed. After integrating out the resonances and assuming a well-behaved high-energy behavior, we estimate or constrain most of the bosonic low-energy constants in terms of only resonance masses. Current fits of these low-energy constants allow us to constrain the high-energy resonance masses.

Speaker: Ignasi Rosell

rosell_EPS_HEP2021.pdf

380 Importance of top quark loop corrections to WW elastic scattering in HEFT

We calculate fermion-loop corrections to high energy $W^+W^-$ scattering in the context of a Strongly Interacting Electroweak Symmetry Breaking Sector (EWSBS) using Higgs Effective Field Theory(HEFT). We test the assumption that these corrections are negligible when compared to the boson-loop ones, as it is commonly taken for granted in the literature. While this is correct in most cases, we find that, for some particular regions of the parameter space of effective couplings, fermion-loops can be important: deviations in the couplings of the HEFT from their Standard Model values may lead to fermion-loop corrections as relevant as the boson-loop ones.

Speaker: Carlos Quezada-Calonge (IPARCOS- Universidad Complutense de Madrid)

EPS2021pdf.pdf

381 SMEFT beyond O(1/Lambda^2)

"In this talk I’ll talk about truncation errors in the Stadard Model Efftective Field Theory (SMEFT) paradigm — meaning errors from higher terms in the EFT expansion. The main tool I’ll use to tackle this type of uncertainty is special operator basis called the “Geometric SMEFT”, or geoSMEFT. I will explain the benefits of the geoSMEFT basis and go through some preliminary studies of the impact of O(1/Lambda^4) terms on observables such as Higgs partial width to photons and Z-pole physics.”

Speaker: Adam Martin (University of Notre Dame)

amartin_EPS_geoSMEFT.pdf

382 EFT description of lepton magnetic and electric dipole moments

In my talk I will present a model-independent analysis of the magnetic and electric dipole moments of the muon and electron. The expressions for the dipole moments are given in terms of operator coefficients of the low-energy effective field theory (LEFT) and the Standard Model effective field theory (SMEFT). One-loop renormalization group improved perturbation theory, including the one-loop matching from SMEFT onto LEFT as well as one-loop lepton matrix elements of the effective-theory operators have been used. Semileptonic four-fermion operators involving light quarks give sizable non-perturbative contributions to the dipole moments, which are included in the analysis. Interestingly only a very limited set of the SMEFT operators is able to generate the current deviation of the magnetic moment of the muon from its Standard Model expectation.

Speaker: Jason Aebischer (UCSD)

eps21_aebischer.pdf

383 Global properties of SMEFT and HEFT

We present two works which study global properties of EFT descriptions of physics beyond the Standard Model (BSM).

The first, based on arXiv:2008.08597, considers what BSM physics is amenable to a decoupling SMEFT description. The four scalar degrees of freedom of the Standard Model, the Higgs and the longitudinal components of the Ws and Z, can be viewed one of two ways: "SMEFT" wraps them up in a single Higgs doublet, whereas "HEFT" treats the Higgs and the Goldstones separately. We identify (field redefinition invariant) features of the scalar field space manifold that can only be described by the latter HEFT, and thereby identify two classes of UV completions for which HEFT is required: i) those which contain extra sources of electroweak symmetry breaking, ii) those which contain particles getting all of their mass from electroweak symmetry breaking.

The second, based on arXiv:2001.00017, considers weakly coupled heavy BSM physics that is amenable to a SMEFT description, and its generic pattern of tree-level and loop-level effects in observables. We do this in the high energy limit, where both the Standard Model and the BSM physics have a specific pattern of effects in helicity amplitudes. A main result is to extend non-interference theorems --- between SM and weakly coupled BSM physics in certain 2 -> 2 scattering processes --- to one-loop order.

Speaker: Dave Sutherland (INFN Sezione di Trieste)

Talk.pdf

384 Combined SMEFT interpretation of Higgs, diboson, and top quark data from the LHC

We present an extensive global interpretation of Higgs, diboson, and top quark production and decay measurements from the LHC in the framework of the Standard Model Effective Field Theory (SMEFT) at dimension six. We constrain simultaneously 36 independent directions in its parameter space, and compare the outcome of the global analysis with that from individual and two-parameter fits. Our results are obtained by means of state-of-the-art theoretical calculations for the SM and the EFT cross-sections, and account for both linear and quadratic corrections in the EFT expansion. We demonstrate how the inclusion of NLO QCD and quadratic effects is instrumental to accurately map the posterior distributions associated to the fitted Wilson coefficients. We assess the interplay and complementarity between the top quark, Higgs, and diboson measurements, deploy a variety of statistical estimators to quantify the impact of each dataset in the parameter space, and carry out fits in BSM-inspired scenarios such as the top-philic model. Our results represent a stepping stone in the ongoing program of model-independent searches at the LHC from precision measurements, and pave the way towards yet more global SMEFT interpretations extended to other high-pT processes as well as to low-energy observables.

Speaker: Juan Rojo (VU Amsterdam and Nikhef)

rojo-SMEFiT-EPSHEP21.pdf

T08: Flavour Physics and CP Violation: Part 5

Conveners: Francesco Dettori (Università degli Studi di Cagliari), Nuno Leonardo (LIP & IST)

385 Charm Status and Prospects at Belle II

The Belle II experiment at the asymmetric $e^+e^-$ collider, SuperKEKB, aims to record 50 ab$^{-1}$ of data over the next decade, a factor of 50 more than Belle. During the first 1.5 years of operations, around 90 fb$^{-1}$ of data were collected. This dataset is used to measure the lifetimes of a few charm hadrons, confirming the expected performance of the Belle II detector, in particular the vertexing, which plays a crucial role in time dependent measurements. Thanks to the performance of the detector and the amount of data that we expect to collect, Belle II will play a crucial role in measuring $CP$ violation and $D^0-\bar{D}^0$ mixing in many decay channels, especially those having neutral particles in the final state. In this presentation we will also show the sensitivity on mixing and CPV parameters in the golden channel $D^0 \to K_S \pi^+ \pi^-$ with a time-dependent Dalitz analysis, and other channels.

Speaker: Mirco Dorigo (BELLE (BELLE II Experiment))

eps2021_talk_mirco_dorigo.pdf

386 Probing Leptophobic $U(1)_H$ Theories at the J-PARC KOTO

$K_L \to \pi \nu \nu $ is one of the attractive processes to test new physics beyond the Standard Model (SM). It is drawing attention, thanks to the effort of the KOTO collaboration. In this talk, we briefly study the $K_L$ decay and other relevant flavor violating processes in a class of type-II two Higgs doublet models with extra gauged $U(1)_H$ symmetry. We sort few examples where the source of missing energy in Kaon decays is given by either dark bosons or massive neutrinos. We focus on the setup where effects of the extra gauge boson and of pseudoscalar portals will emerge primarily at the electroweak penguin level of $\Delta F = 1,2$ processes. We show that J-PARC KOTO most stringent upper limit for the branching ratio of $K_L \to \pi \nu \nu $ leads to important bounds for leptophobic and multi-Higgs $SM \otimes U(1)_X$ theories, at or below the electroweak scale, comparable to the limits provided by hadron colliders.

Speaker: Fagner Cintra Correia (Korea Institute for Advanced Study)

387 Rare and forbidden decays of D0 meson.

We report the observation of the rare charm decay $D^0 \to K^-\pi^+e^+e^-$, a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type $D^0 \rightarrow h^- h^{'-} \ell^+ \ell^{'+}$, and $D^0 \rightarrow h^- h^{'+} \ell^+ \ell^{'-}$, and a search for seven lepton-number-violating decays of the type $D^{0}\rightarrow X^{0} e^{\pm} \mu^{\mp}$, where $h$ and $h^{\prime}$ represent a $K$ or $\pi$ meson, $\ell$ and $\ell^{\prime}$ an electron or muon, and $X^{0}$ a $\pi^0$, $K^0_S$, $K^{*0}$, $\rho^{0}$, $\phi$, $\omega$, or $\eta$ meson. The results, which greatly improve on previously available data, are based on $468$ fb$^{-1}$ of $e^+e^-$ collision data collected at or close to the $\Upsilon(4S)$ resonance with the BaBar detector at the SLAC National Accelerator Laboratory.

Speaker: Fabio Anulli (INFN Sezione di Roma)

Anulli-EPS-HEP-2021.pdf

388 Leptonic and semileptonic D decays at BESIII

BESIII has collected 2.9 and 6.3 fb-1 of e+e- collision data samples at 3.773 and 4.178-4.226 GeV, respectively. We report recent measurements of the (semi)leptonic decays D(s) -> l+nu (l=mu, tau) and D(s) -> X l+nu [X=K(*), rho, eta('), a_0, K_1, and l=e, mu]. The decay constants f_D(s), the semileptonic form factors f(0) and the CKM matrix elements |V_cs(d)| are determined precisely. These results are important to verify the LQCD calculations of f_D(s) and f(0) and the CKM matrix unitarity. Precision tests of lepton-flavor universality with (semi)leptonic D decays are also made.

Speaker: Ke Liu (HAUT)

EPS-LIUKE_v3.pdf

389 Measurement of the very rare K^+→π^+ νν ̅ decay with the NA62 Experiment at CERN

The decay K^+→π^+ νν ̅, with a very precisely predicted branching ratio of less than 〖10〗^(-10), is among the best processes to reveal indirect effects of new physics. The NA62 experiment at CERN SPS is designed to study the K^+→π^+ νν ̅ decay and to measure its branching ratio using a decay-in-flight technique. NA62 took data in 2016, 2017 and 2018, reaching the sensitivity of the Standard Model for K^+→π^+ νν ̅ by the analysis of the 2016 and 2017 data, and providing the most precise measurement of the branching ratio to date by the analysis of the 2018 data. This measurement is also used to set limits on the branching ratio of a possible K^+→π^+ X decay, where X is a scalar or pseudo-scalar particle. The final result of the K^+→π^+ νν ̅ branching ratio measurement and its interpretation in terms of K^+→π^+ X decay from the analysis of the full 2016-2017-2018 data set is presented, and future plans and prospects reviewed.

Speaker: Angela Romano (University of Birmingham)

AngelaRomano_EPS_HEP2021.pdf

390 Flavour Physics and CP Violation at KLOE-2

KLOE-2 experiment at the upgraded e+e- DAΦNE collider of the INFN Laboratori Nazionali di Frascati collected about 5 fb$^{-1}$ at the center of mass energy of the $\phi$-meson. Together with the data set of its predecessor (KLOE) the total acquired data sample of 8 fb$^{-1}$ corresponds to 2.4$\times$10$^{10}$ $\phi$-meson produced, which is the largest sample ever collected at the $\phi$(1020) at e$^+$e$^−$ colliders.

The KLOE-2 Collaboration continues the KLOE long-standing tradition of flavour physics precision measurements in the kaon sector and search for Physics Beyond the Standard Model.

In this talk the latest results on $K_S$ rare decays are presented and discussed in the framework of Flavour Physics and CP Violation tests, among these the measurement of $K_S$ semileptonic branching ratios, using 1.7 fb$^{-1}$ KLOE data, and the search for the pure CP-violating $K_S\to3\pi^0$ decay with the KLOE-2 data set.

Speaker: Aleksander Gajos (Jagiellonian University)

gajos_talk.pdf

391 LHCb results in charm baryons

The LHCb experiment collected the world's largest sample of charmed hadrons during LHC Run 1 and Run 2. With this data set, LHCb is currently providing the world's most precise measurements of properties and production of known charmed baryons, as well as discovering many previously unobserved states. The latest results from the LHCb Collaboration on charmed baryons are presented.

Speaker: Ao Xu (Peking University)

axu_eps_2107_v2.pdf

392 Mixing and time-dependent CPV in charm decays at LHCb

LHCb has collected the world's largest sample of charmed hadrons. This sample is used to measure $D^0 -\overline{D}^0$ mixing and to search for $C\!P$ violation in mixing and interference. New measurements from several decay modes are presented, as well as prospects for future sensitivities.

Speaker: Dr Federico Betti

betti_federico_v2.pdf

T10: Searches for New Physics: Part 6

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Pedro Schwaller (Johannes Gutenberg University Mainz)

393 Non-Resonant Searches for Axion-Like Particles at the LHC

We discuss non-resonant ALP-mediated diboson production, a collider probe for axion-like particles (ALPs) which takes advantage of the derivative nature of their interactions with Standard Model particles; here ALPs participate as off-shell mediators of 2 → 2 scattering processes at colliders like the LHC. The power of this novel type of search was first tested by deriving limits on ALP couplings to gauge bosons via processes like gg → ZZ using Run 2 CMS public data, probing previously unexplored areas of the ALP parameter space. Other non-resonant searches involving the ALP couplings to other electroweak bosons and/or the Higgs particle are presented. LHC experiments are now searching for these processes using the full Run 2 data samples. In addition, new studies on non-resonant ALP-mediated Vector-Boson Scattering (VBS) and preliminary results based on recently published CMS data are presented. Expectations for LHC Run 3 and HL-LHC are derived.

Speaker: Jorge F. de Trocóniz

troconiz_ALP_VBS_EPS.pdf

394 The Anomalous Case of Axion EFTs and Massive Chiral Gauge Fields

We study axion effective field theories (EFTs), with a focus on axion couplings to massive chiral gauge fields. We investigate the EFT interactions that participate in processes with an axion and two gauge bosons, and we show that, when massive chiral gauge fields are present, such interactions do not entirely originate from the usual anomalous EFT terms. When applied to the case of the Standard Model (SM) electroweak sector, our results imply that anomaly-based sum rules between EFT interactions are violated when chiral matter is integrated out, which constitutes a smoking gun of the latter. As an illustration, we study a UV-complete chiral extension of the SM, containing an axion arising from an extended Higgs sector and heavy fermionic matter that obtains most of its mass by coupling to the Higgs doublets. We assess the viability of such a SM extension through electroweak precision tests, bounds on Higgs rates and direct searches for heavy charged matter. At energies below the mass of the new chiral fermions, the model matches onto an EFT where the electroweak gauge symmetry is non-linearly realised.

Speaker: Alejo Rossia (T (Phenomenology))

Rossia_Axion_EPS_2021.pdf

395 The new ``MUON G-2'' Result and Supersymmetry

We confront the Minimal Supersymmetric Standard Model (MSSM) with the recent measurement of (g-2)_mu, the Dark Matter (DM) relic density, DM direct detection limits and electroweak SUSY searches at the LHC. We demonstrate that various distinct regions of the parameter space can fulfill all experimental constraints. We present predictions for future pp and e+e- colliders to explore these regions.

Speaker: Dr Manimala Chakraborti (Astrocent, Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences)

Chakraborti_EPSHEP_21 1.pdf

396 New physics explanations of $a_\mu$ in light of the FNAL muon $g-2$ measurement

The Fermilab Muon $g-2$ experiment reported the results of its Run-1 measurement of the anomalous magnetic moment $a_\mu^{\textrm{FNAL}}$, which is in full agreement with the previous BNL measurement and pushes the world average deviation $\Delta a_\mu^{\text{2021}}$ from the Standard Model to a significance of $4.2\sigma$. In this talk I will present an extensive survey of its impact on beyond the Standard Model physics, based on the work in Ref. [1]. In this work we used state-of-the-art calculations and a sophisticated set of tools to make predictions for $a_\mu$, dark matter and LHC searches. We examined a wide range of simple models with up to three new fields, that represent some of the few ways that large $\Delta a_\mu$ can be explained. The results show that the new measurement excludes a large number of models and provides crucial constraints on others. Generally, these models provide viable explanations of the $a_\mu$ result only by using rather small masses and/or large couplings with chirality flip enhancements, which can lead to conflicts with limits from LHC and dark matter experiments. I will present results for a range of models including scalar leptoquarks and simple models constructed to explain dark matter and g-2 simultaneously.

[1] Athron P, Balázs C, Jacob D H, Kotlarski W, Stöckinger D and Stöckinger-Kim H 2021 (Preprint 2104.03691)

Speaker: Douglas Jacob (Monash University)

Douglas Jacob EPS-HEP Presentation.pdf

397 Light Scalar and Lepton Anomalous Magnetic Moments

Recent precise determination of the electron anomalous magnetic moment (AMM) adds to the longstanding tension of the muon AMM and together strongly point towards physics beyond the Standard Model. Here we present a solution to both anomalies via a light scalar that emerges from a second Higgs doublet and resides in the $\mathcal{O}(10)$-MeV to $\mathcal{O}(1)$-GeV mass range. A scalar of this type is subject to a number of various experimental constraints, however, as we show, it can remain sufficiently light by evading all experimental bounds and has the great potential to be discovered in the near-future low-energy experiments. In addition to the light scalar, our theory predicts the existence of a nearly degenerate charged scalar and a pseudoscalar, which have masses of the order of the electroweak scale. This scenario can be tested at the LHC by looking at the novel process $pp \to H^\pm H^\pm jj \to l^\pm l^\pm j j + {E\!\!\!\!/}_{T}$ via same-sign pair production of charged Higgs bosons.

Speaker: Vishnu Padmanabhan Kovilakam (Oklahoma State University)

leptonAMM_lightscalar_EPS2021.pdf

398 Physics Beyond the Standard Model with the J-PET detector

The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the hydrogen system, is not affected by finite size or QCD effects at current experimental precision level. This makes the Ps atom a good laboratory to test the Fundamental Symmetries of Physics and also search for new particles not included in the Standard Model (SM) of physics.

On one hand, time reversal (T) and CP symmetry violation have never been observed in pure leptonic systems like the Ps atom, and the current experimental limits for CP and CPT violation in the decays of Ps is currently set at the level of 10$^{-3}$, while for C violation are at the level of 10${7}$. This limits are still six and two orders of magnitude lower than the expected precision of 10$^{-9}$ set by photon-photon interactions. Secondly, experiments searching for invisible decays of the Ps triplet state, the ortho-Positronium (o-Ps), which mainly decays to three photons, are being conducted, since they are sensitive to new physics scenarios, e.g. Mirror Matter (MM), a suitable Dark Matter candidate, proposed to restore parity (P) violation. By performing a high precision measurement of the o-Ps lifetime, the accuracy of the present QED calculations can be tested and a search for the invisible decays of the o-Ps conducted.

These studies are conducted with the novel total-body Positron-Electron Tomograph (PET) scanner at he Jagiellonian University. The J-PET is a large and high precise medical imaging tool, based on the plastic scintillators. The J-PET is a high acceptance multi-purpose detector optimized for the detection of photons from positron-electron annihilation and can be used in a broad scope of interdisciplinary investigation, e.g. medical imaging, life-time measurements, quantum entanglement studies with o-Ps, and tests of discrete symmetries.

Speaker: Elena Perez del Rio

eps_EPR_JPET.pdf

399 Unification of Gauge Symmetries ... including their breaking

In this talk, we present a minimal viable scenario that unifies the gauge symmetries of the SM and their breaking sector. Our Gauge-Higgs Grand Unification setup employs 5D warped space with a SU(6) bulk gauge field that includes both a SU(5) grand unified theory (GUT) and a Higgs sector as a scalar component of the 5D vector field, solving the hierarchy problem. By appropriately breaking the gauge symmetry on the boundaries of the extra dimension the issue of light exotic new states, appearing generically in such models, is eliminated and the SM fermion spectrum is naturally reproduced. The Higgs potential is computed at one-loop, finding straightforward solutions with a realistic mh = 125 GeV. The problem of proton decay is addressed by showing that baryon number is a hidden symmetry of the model. The presence of a scalar leptoquark and a scalar singlet is highlighted, which might play a role in solving further problems of the SM, allowing for example for electroweak baryogenesis. Finally, the X and Y gauge bosons from SU(5) GUTs are found at collider accessible masses, opening a window to the unification structure at low energies.

Speaker: Florian Goertz (MPIK)

EPS21_Goertz.pdf

400 Hierarchy in double SU(2) models

In this work, we provide a simple model in order to compute the probability to obtain a given hierarchy between two scales. In particular, we work in a model with a given gauge symmetry and two scalar doublets. By the Coleman-Weinberg mechanism, the gauge bosons and scalars obtain different masses, corresponding to the light and heavy sectors. We analyze the mass ratio of these sectors in order to discuss the hierarchy between them, and we define a probability associated to this hierarchy. We analyze different cases in which one of the sectors is fixed or both of them have free parameters, and also study the effect of including an interaction between them. We conclude that the probability of obtaining very large hierarchies is not negligible.

Speaker: Clara Álvarez Luna (Universidad Complutense de Madrid)

slides-ClaraÁlvarezLuna.pdf

T12: Detector R&D and Data Handling: Trigger/Readout/Reconstruction

Conveners: Annika Vauth (Universität Hamburg), Magnus Mager (CERN)

401 Online DAQ and slow control interface for the Mu2e experiment

The muon campus program at Fermilab includes the Mu2e experiment that will search for a charged-lepton flavor violating processes where a negative muon converts into an electron in the field of an aluminum nucleus, improving by four orders of magnitude the search sensitivity reached so far.
Mu2e’s Trigger and Data Acquisition System (TDAQ) uses {\it otsdaq} as its solution. Developed at Fermilab, {\it otsdaq} uses the {\it artdaq} DAQ framework and {\it art} analysis framework, under-the-hood, for event transfer, filtering, and processing.
{\it otsdaq} is an online DAQ software suite with a focus on flexibility and scalability, while providing a multi-user, web-based, interface accessible through a web browser.
A Detector Control System (DCS) for monitoring, controlling, alarming, and archiving has been developed using the Experimental Physics and Industrial Control System (EPICS) open source Platform. The DCS System has also been integrated into {\it otsdaq}.

Speaker: Antonio Gioiosa (Universitiy and INFN Pisa)

AG_EPS-HEP_July28_2021.pdf

402 Preparation for ALICE data processing and analysis in LHC Run 3

After the ALICE Long Shutdown 2 detector upgrades, including a new silicon tracker and a GEM-based readout for the TPC, the experiment will operate during LHC Run 3 at a peak Pb-Pb collision rate of 50 kHz, about 50 times higher than in previous running periods. To maximise the significance of physics signals with low S/B ratios for which triggering is not possible, all events will be read out and written to permanent storage without any selective trigger. In order to minimise the costs and computing time of the online and offline systems, data volume reduction is performed synchronous with data taking on the newly installed Online/Offline facility O2. The facility consists of two types of compute nodes, the First Level Processors (FLP) and the Event Processing Nodes (EPN). Each FLP receives data from parts of individual detectors, performs a first level of data compression by zero suppression as well as calibration tasks, and sends its output to the EPNs over an Infiniband network. Using the EPN's CPU cores and GPUs, data is reconstructed and further compressed. Moreover, data for detector calibration is created. Online data processing is followed by offline reconstruction passes using fully calibrated data producing the input for data analysis (AOD). In addition, large samples of simulated data as input for detector response and performance studies will be produced.

Here we describe the data processing chain and give an overview of the design choices and implementations for the newly developed software frameworks, which can cope with the unprecedented data rates and volumes. The status of the preparation for data processing and analysis in view of the first physics runs in 2022 is presented.

Speaker: Giulio Eulisse

2021-07-eps-data-processing.pdf

403 FELIX and the SW ROD: commissioning the new detector interface for the ATLAS trigger and readout system

After the current LHC shutdown (2019-2022), the ATLAS experiment will be required to operate in an increasingly harsh collision environment. To maintain physics performance, the ATLAS experiment is undergoing a series of upgrades. A key goal of this upgrade is to improve the capacity and flexibility of the detector readout system. To this end, the Front-End Link eXchange (FELIX) system has been developed. FELIX acts as the interface between the data acquisition; detector control and TTC (Timing, Trigger and Control) systems; and new or updated trigger and detector front-end electronics. The system functions as a router between custom serial links from front end ASICs and FPGAs to data collection and processing components via a commodity switched network. The serial links may aggregate many slower links or be a single high bandwidth link. FELIX also forwards the LHC bunch-crossing clock, fixed latency trigger accepts and resets received from the TTC system to front-end electronics. FELIX uses commodity server technology in combination with FPGA-based PCIe I/O cards. FELIX servers run a software routing platform serving data to network clients. Commodity servers connected to FELIX systems via the same network run the new multi-threaded Software Readout Driver (SW ROD) infrastructure for event fragment building, buffering and detector-specific processing to facilitate online selection. This presentation will cover the design of FELIX and the SW ROD, as well as the results of the installation and commissioning activities for the full system in spring 2021.

Speaker: William Panduro Vazquez (Royal Holloway, University of London)

FELIX and the SW ROD.pdf

404 ATLAS toward the High Luminosity era: challenges on electronic systems

To maximize the physics reach, the LHC plans to increase its instantaneous luminosity to $7.5\times10^{34}$cm$^{-2}$s$^{-1}$, delivering from 3 to 4 ab$^{-1}$ of data at $\sqrt{s}=$14TeV. In order to cope with this operation condition, the ATLAS detector will require new sets of both front-end and back-end electronics. A new trigger and DAQ system will also be implemented with a single-level hardware trigger featuring a maximum rate of 1 MHz and 10μs latency. Enhanced software algorithms will further process and select events, storing them at a rate of 10 kHz for offline analysis. The large number of detector channels, huge volumes of input and output data, short time available to process and transmit data, harsh radiation environment and the need of low power consumption all impose great challenges on the design and operation of electronic systems. This talk will focus on these challenges, the proposed solutions and the latest results obtained from the prototypes.

Speaker: Dr Carlos Solans Sanchez (CERN)

Carlos_EPS_20210728_10.pdf

405 Overview of the HL-LHC Upgrade for the CMS Level-1 Trigger

The High-Luminosity LHC will open an unprecedented window on the weak-scale nature of the universe, providing high-precision measurements of the standard model as well as searches for new physics beyond the standard model. Such precision measurements and searches require information-rich datasets with a statistical power that matches the high-luminosity provided by the Phase-2 upgrade of the LHC. Efficiently collecting those datasets will be a challenging task, given the harsh environment of 200 proton-proton interactions per LHC bunch crossing. For this purpose, CMS is designing an efficient data-processing hardware trigger (Level-1) that will include tracking information and high-granularity calorimeter information. Trigger data analysis will be performed through sophisticated algorithms such as particle flow reconstruction, including widespread use of Machine Learning. The current conceptual system design is expected to take full advantage of advances in FPGA and link technologies over the coming years, providing a high-performance, low-latency computing platform for large throughput and sophisticated data correlation across diverse sources.

Speaker: Varun Sharma

2021-07-EPS-L1T-VS.pdf

406 A GPU High Level Trigger 1 for the upgraded LHCb detector

In 2022 the upgraded LHCb experiment will use a triggerless readout system collecting data at an event rate of 30 MHz. A software-only High Level Trigger will enable unprecedented flexibility for trigger selections. During the first stage (HLT1), a sub-set of the full offline track reconstruction for charged particles is run to select particles of interest. After this first stage, the event rate is reduced by at least a factor 30. Track reconstruction at 30 MHz represents a significant computing challenge, requiring a renovation of current algorithms and the underlying hardware. In this talk, we present the approach of executing the full HLT1 chain on GPUs. This includes decoding the raw data, clustering of hits, pattern recognition, as well as track fitting. We discuss the design of HLT1 algorithms optimized for many-core architectures. Both the computing and physics performance of the full HLT1 chain will be presented.

Speaker: Marianna Fontana

MFontana_GPU.pdf

407 Real-time analysis in Run 3 with the LHCb experiment

Second stage of high-level trigger at the LHCb, deployed on a CPU server farm, not only selects events but performs an offline-quality alignment and calibration of the detector and uses this information to allow physics analysts to deploy essentially their full offline analysis level selections (including computing isolation, flavour tagging, etc) at the trigger level. This “real time analysis” concept has also allowed LHCb to fully unify its online and offline software codebases. We cover the design and performance of the system which will be deployed in Run 3, with particular attention to the physics performance of the new algorithms.

Speaker: Peilian Li (Heidelberg University)

RTA_LHCb_EPS_PeilianLi_v2.pdf

T14: Outreach, Education and Diversity: Part 2

408 The Women in Technology grass roots community at CERN – an example of women networking in a scientific organisation

The creation of scientific knowledge has transitioned from largely solitary work to collective efforts embedded in large collaborations, placing a new emphasis on social networks as the mechanism linking interdependent scientists across departments and universities. Professional networks have proven to be a key contributor in the career success and their presence becomes even more important for underrepresented communities. In this context, the Women in Technology community at CERN (WIT) was born in the early 2016. At the time, two new members of the IT Department started this grass roots community when realized that women networks from which they had benefited at university and in industry did not exist at CERN, or in the local area.

The main aim of the WIT community is to create a supportive network for exchanging experiences and career advice among women working at CERN. It came on the scene to complement the other professional community networks within he diverse CERN environment, like LGBTQ network and country networks. WIT activites span on different fronts: interviews featuring senior women scientists to inspire the younger generation, social events such as movie screenings and aboratory visits, and a yearly mentoring scheme between more experienced members as mentors and less experienced ones as mentees. Moreover it also strengthens the visibility of women scientists in local schools through outreach lectures and events. The WIT community today comprises more than 500 members, has organised three mentoring yearly programmes and is present in multiple outreach events, both in the local area and world wide through social media.

Women networks, such as WIT, are beneficial to both the network participants and the organisation as a whole: not only do they provide a place to connect and share common experiences but also they can interface with CERN internal programs, such as CERN’s official Diversity & Inclusion, transfering the community’s ideas and advocating for minoriy’ issues. It has to be noted that even if WIT was born in the spirit of supporting women, it actually welcomes members from all genders and all technical fields.

This contribution describes how WIT is structured and the different activities organised by the community; it also highlights how networks like WIT contribute to making an impact on diversity and inclusion in a scientific research organisation like CERN.

Speaker: Maria Alandes Pradillo (CERN)

EPS-HEP-WIT-slides.pdf

409 Diversity and Inclusion at Belle II

The Belle II collaboration has over 1000 people from institutions in 26 countries working together to achieve its physics goals. The collaboration is committed to fostering an open, diverse, and inclusive environment, and created a diversity office to raise awareness of diversity and inclusion issues, promote an inclusive atmosphere within the collaboration, provide a safe and confidential point to contact for collaborators to report any issues, particularly those related to discrimination and harassment, and ensure that persons from underrepresented groups are considered for positions of responsibility within the collaboration. This presentation will discuss diversity and inclusion activities and initiatives at Belle II, and present an analysis of the evolving demographics of the collaboration.

Speaker: Shanette Anne De Lamotte (BELLE (BELLE II Experiment))

CompanionScript_DiversityAndInclusionActivitiesAtBelleII.pdf

Diversity and inclusion activities at the Belle II.pdf

410 ATLAS Open Data –a genuinely collaborative approach for the creation of educational resources

The ATLAS Open Data project aims to deliver open-access resources for education and outreach in High Energy Physics and related computer sciences. Because the resources -data, software and documentation-target students and instructors, they must be tested by students and instructors before being released. One of the most effective production ways we have found is to promote on-site and remote training schemes such as high-school work experience and summer schools programs, university projects and PhDs qualification tasks. Those programs and alliances allow the construction of a platform that relies on the expertise of ATLAS members and the invaluable contribution of students that help to test and build resources that hundreds of their peers use around the world. We present how multiple training programs inside and outside CERN helped and continue to help create the ATLAS Open Data project and the lessons learnt so far on how to continue implementing this kind of programs.

Speaker: Meirin Oan Evans (University of Sussex)

EPS.pdf

EPS.pptx

411 The Early Career, Gender & Diversity at LHCb

LHCb is a collaboration of over 1300 members from 83 institutions based in 19 countries, and representing many more nationalities. We aim to work together on experimental high energy physics, and to do so in the best and most collaborative conditions. The Early Career, Gender & Diversity (ECGD) office exists to support this goal, and in particular has a mandate to support early-career (EC) physicists, thanks also to the recent addition of two EC representatives, to work towards gender equality, and support diversity in the collaboration. The ECGD officers advise the LHCb management and act as LHCb contacts for all matters related to ECGD. They are available for listening to and advising - in a confidential manner - colleagues who have witnessed or have been subject to harassment, discrimination or other inappropriate behaviour. They help raise awareness in the collaboration for topics related to ECGD. In this talk we briefly introduce the ECGD office, discuss what we have learnt from analysis of the collaboration's demographics and responses from a survey that we conducted recently on the impact of covid-19 on our community. Finally, we will share our experience gained over the last years, and we present our vision for the future evolution of the ECGD.

Speaker: Francesca Dordei (University of Cagliari)

ECGD_EPS_2.pdf

412 The importance of visual representation

Science communication is a field that has been evolving over the years. Visual communication has proved to be a critical allied for communication and outreach. The democratisation of technology, the development of 4G / 5G, and social media establishment pushed visual communication as a vital tool for any communication strategy. In large research organizations such as CERN, the archive of images, articles, and videos are not only part of their heritage and memory, it is also a communication tool. A healthy image database open to everyone is key to facilitate assets for user-generated content. In a knowledge-intensive organization, it is important to balance the audiovisual archive needs as technologies evolve and the demand for content creation. With images, diversity can be shown without explaining it. I want to go through my experience at CERN as a videographer and photographer from 2013 to 2020, during the explosion of social media and user-generated content, and talk about the importance of creating images for others to be used on their articles, press assets, presentations and their social media publications. I would like to set the example of the work done with the WIT group at CERN and the importance of being involved in diverse groups to make them part of the conversation. WIT members will explain how important these images are for their communication strategy and their social media impact.

Speaker: Noemi Caraban

WomeninScience.key

413 How to use your smartphone for outreach

The best camera is the one you have on you.

In this tutorial, I will discuss how to use a smart phone to communicate your work with a remote audience using the inbuilt camera to produce still images and video content. This can then be edited, if needed, and shared on various social media platforms. Alternatively you can use your phone to directly live-stream and interact with your audience in real-time.

We will explore how to make sure what you are sharing will be accessible and consider which platforms are better for different forms of content. Finally we will look at how to evaluate the different types of feedback from the platforms and the audience.

Speaker: Clara Nellist (Radboud University Nijmegen and NIKHEF (NL))

2021-07-28_EPS_Outreach_CNellist.pdf

2021-07-28_EPS_Outreach_CNellist.pptx

414 Physics Live on Social Media: Good Practices to Engage New Audiences and Support Education

Early in 2020, as the Covid-19 pandemic started to hit Europe, scientific outreach and education had to face a new challenge: finding rapidly new ways to engage general public and students. Social media were found to be a useful tool to achieve this goal: thousands of people could be reached directly at home with a few clicks by using a laptop or a mobile phone.
In this talk, it will be discussed how to efficiently organize a series of live events dedicated to schools to be run on Facebook and YouTube and how to, complementary, organize informal lives for Instagram on cutting-edge physics topics to engage a broader and more general audience.
To do so, some useful tools to set up live events will be presented and some guidelines on how to outline them will be summarized. Most of all, it will be discussed how to stimulate and deal with interaction of the audience, a fundamental feature of communication on social media. Finally, some good communication practices to invite people to join the lives will be shown.
The talk will be enriched by practical examples: it will be described how INFN, the Italian National Institute for Nuclear Physics, stood up to this new challenge, by strengthening its communication on Instagram to engage new audiences and by promptly organizing a series of live events on social media for high school students to support the school program and to offer insights on modern physics, from particle and astroparticle physics to cosmology.

Speaker: Francesca Mazzotta (INFN)

EPS_OutreachEduDiversity_Mazzotta.pdf

11:30 Lunch Break

Plenary Session 2

Convener: Federico Antinori

415 Highlights from the LHCb Experiment

Speakers: Franz Muheim, Franz Muheim (University of Edinburgh)

LHCb-highlights-EPS2021-Muheim-vfinal.pdf

recording

416 Highlights from the ALICE Experiment

Speaker: Klaus Reygers (University of Heidelberg)

ALICE-highlights-EPS-HEP-2021.pdf

recording

417 Beyond Standard Model Theory

Speaker: Anson Hook

AH_EPS.pdf

recording

418 Quantum Field and String Theory

Speaker: Juan Maldacena

EPSTalk2021.pdf

recording

Plenary Session 2: special g-2 session

Convener: Anna Lipniacka

419 g-2: Theory overview

Speaker: Gilberto Colangelo

Colangelo_g-2_EPS2021.pdf

recording

420 Fermilab muon g-2 result and future perspectives 15’

Speaker: Alex Keshavarzi (University of Manchester)

AKeshavarzi_EPSHEP_28-07-21-compressed.pdf

recording

421 Discussion

15:15 Break

Review Stream 1: Session 2

Convener: Thomas Gehrmann (University of Zurich)

422 Standard Model Measurements

Speaker: Paolo Azzurri

azzurri_SMreview_EPSHEP21.pdf

recording

423 Searches for Exotica

Speaker: Andreas Hinzmann (University of Hamburg)

210728 - Searches for exotica.pdf

recording

Review Stream 2: Session 2

Convener: Mauro Mezzetto

424 Cosmic Messengers

Speaker: Irene Tamborra (Niels Bohr Institute)

EPS2021_Tamborra.pdf

425 Cosmology and Dark Matter Theory

Speaker: Tracy Slatyer

recording

Slatyer_DMTheory_EPS-HEP_2021.pdf

16:30 Break

Additional Poster Session

All rooms are open and the posters can be watched, but the presenters might not be next to their posters. There will be limited technical support.

Click here to access the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions).

Please also check the information how to enter and navigate the rooms on our main conference web page.

Access to the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions)

T01: Astroparticle and Gravitational Waves: Part 6

Convener: Walter Del Pozzo (University of Pisa)

426 Gravitational waves searches in O3 Advanced LIGO and Advanced Virgo data

Third Observation (O3) run of Advanced LIGO and Advanced Virgo started in April 2019 and ended in March 2020; reaching sensitivities significantly better than those in the previous observing run. During this period, 56 gravitational-wave candidates were publicly released within hours of detection.
This talk will overview the published science results achieved during the O3 run, focusing on the catalog of the gravitational waves signal due to compact binary coalescences (GWTC-2) and on the main outcomes of follow-up investigations, e.g. tests of general relativity. Among gravitational waves signals reported in GWTC-2, a few have been associated to exceptional scientific case such as binary system with significantly asymmetric mass ratios (GW190412), or intermediate-mass black holes (GW190521), these will be discussed.

Speaker: Claudia Lazzaro (Università degli Studi di Padova)

EPS21_Lazzaro.pdf

427 Multimessenger Analysis Strategy for Core-Collapse Supernova Search: Gravitational Waves and Low-energy Neutrinos

Core-collapse supernovae are fascinating astrophysical objects for multimessenger studies. Gravitational waves (GWs) are expected to play a role in the supernova explosion mechanism, but their modelling is also challenging due to the stochastic nature of the dynamics and the vast possible progenitors, and moreover, the GW detection from these objects is still elusive with the already advanced detectors. Low-energy neutrinos will be emitted enormously during the core-collapse explosion and can help for the gravitational wave counterpart search. In this work we develop a multi-messengers strategy to search for such astrophysical objects by exploiting a global network of both low-energy neutrino and gravitational wave detectors. First, we discuss how to improve the detection potential of the neutrino sub-network by exploiting the temporal behaviour of a neutrino burst from a core-collapse supernova. Then, we combine the information provided by GW and neutrino in a multi-messenger strategy. Our method can better disentangle from noise the low statistical signals coming from weak (or far) supernovae giving us about $10^3$ lower \textit{false-alarm-probability} for recovered signal injections.

Carlo Vigorito, Claudio Casentini, Giulia Pagliaroli, Marco Drago, Odysse Halim, and Viviana Fafone

Speaker: Odysse Halim

210726_EPS_meeting.pdf

428 Mind the gap: What can we learn about stellar astrophysics from gravitational wave detections of binary black holes?

With the detection of binary black hole (BH) mergers from LIGO/Virgo we have opened up the field of gravitational wave astronomy and created a new window into the Universe. These discoveries bring new and independent information about how very massive stars end their life, and the final remnants they leave behind. In this talk I will discuss the stellar physics that goes into the formation of the most massive stellar mass black holes and how the detection of most massive merging pair of black holes to date, GW190521, with both BHs being in the “PISN mass gap” challenges this picture. I will show what physics goes into the location of this mass gap, and how robust we believe the estimate of the location of the mass gap is. I will then discuss what GW190521 informs us about the location of the mass gap, and the implications for finding both black holes in the mass gap. Finally, I will also discuss how measuring the location of the mass gap allows us to place constraints on uncertain stellar physics, namely the C12(alpha,gamma)O16 nuclear reaction rate and what GW190521 can tell us about this nuclear reaction rate.

Speaker: Rob Farmer (University of Amsterdam)

rfarmer_epshep.pdf

T04: Neutrino Physics: Neutrinoless double beta decay

Convener: Bjoern Soenke Wonsak (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik))

429 Final results of GERDA on the search for neutrinoless double beta decay

The GERDA (GERmanium Detector Array) collaboration operated high-purity Ge detectors enriched in $^{76}$Ge at LNGS to search for neutrinoless double beta decay ($0\nu\beta\beta$). An observation would imply both the Majorana nature of neutrinos and the violation of lepton number conservation, with important consequences for the neutrino mass scale, and the matter-antimatter asymmetry in the Universe. The operation of high resolution Ge detectors in an active liquid Ar shield combined with a powerful pulse shape discrimination allowed the collection of a background-free data set. With a total exposure of 127.2 kg yr, a lower limit on the half-life of $0\nu\beta\beta$ in $^{76}$Ge of $T_{1/2} > 1.8 \times 10^{26}$ yr at 90% C.L was set, a world-leading constraint in the search for $0\nu\beta\beta$. In this talk I will give an overview of the experimental techniques exploited to reach the final result.

Speaker: Yannick Müller (Physik-Institut, University of Zurich)

GERDA_EPS2021.pdf

430 The Large Enriched Germanium Experiment for Neutrinoless Double-Beta Decay

The observation of neutrinoless double-beta ($0\nu\beta\beta$) decay would unequivocally demonstrate that lepton number conservation is violated and that neutrinos are Majorana particles. Such a discovery would have profound consequences for particle physics and cosmology.

The Large Enriched Germanium Experiment for Neutrinoless $\beta\beta$ Decay (LEGEND) collaboration has been formed to pursue a ton-scale $^{76}$Ge-based $0\nu\beta\beta$ decay experimental program with discovery potential at a half-life beyond $10^{28}$ years. LEGEND is building on the success of the predecessor experiments GERDA and Majorana Demonstrator which have achieved both the best energy resolution and lowest background in the field.

The first 200-kg phase (LEGEND-200) is currently under construction at the Gran Sasso underground laboratory (Laboratori Nazionale del Gran Sasso, Italy) and will be commissioned later this year. In this contribution I will present the current status of LEGEND-200 as well as the prospects of the proposed ton-scale phase LEGEND-1000.

The material in this contribution is based upon work supported by the U.S. NSF, DOE-NP, NERSCC and through the LANL & LBNL LDRD programs, and the Oak Ridge Leadership Computing Facility; the Russian RFBR, the Canadian NSERC and CFI; the German BMBF, DFG and MPG; the Italian INFN; the Polish NCN and Foundation for Polish Science; and the Swiss SNF; the Sanford Underground Research Facility, and the Laboratori Nazionali del Gran Sasso.

Speaker: Michael Willers (Technische Universität München)

20210728 - MWillers - The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay.pdf

431 NEXT: Measurement of the 136Xe two-neutrino double beta decay half-life with NEXT-White

The NEXT (Neutrino Experiment with a Xenon TPC) collaboration aims at the sensitive search of the neutrino-less double beta decay (ββ0ν) of 136Xe at the Laboratorio Subterraneo de Canfranc (LSC). The observation of such a lepton-number-violation process would prove the Majorana nature of neutrinos, providing also handles for an eventual measurement of the neutrino absolute mass. A first large-scale prototype of a high-pressure gas-Xenon electrolumines- cent TPC, NEXT-white, is being operated at the LSC since 2016. This 5-kg ra- diopure detector has already proven the outstanding performance of the NEXT technology in terms of the energy resolution (<1% FWHM at 2.6 MeV) and the topology-based background rejection. NEXT-White has also measured the relevant backgrounds for the ββ0ν search using both 136Xe-depleted and 136Xe- enriched xenon. In this talk, the measurement of the half-life of the two neutrino mode of the double beta decay (ββ2ν) will be presented. For this measurement, two novel techniques in the field have been used: 1) a Richardson-Lucy de- convolution to reconstruct the single and double electron tracks, boosting the background rejection, and 2) a direct subtraction of the ββ backgrounds, mea- sured with 136Xe-depleted data. These techniques allow for background-model- dependent and background-model-independent results, demonstrating the ro- bustness of the ββ2ν half-life measurement and the unique capabilities of NEXT. The physics program of NEXT-White will be completed in late 2021, when the construction of the NEXT-100 detector at the LSC starts. Holding 100 kg of 136Xe and with a background index below 5×10−4 counts/keV/kg/year, this detector will perform the first competitive ββ0ν search within the NEXT roadmap. As validated with NEXT-White, NEXT-100 will reach a sensitivity to the half-life of 6×1025 y after 3 years of data taking.

Speaker: Pau Novella (IFIC)

NEXT_EPS2021.pdf

432 Latest results from the CUORE experiment

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has been able to reach the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of about 10 mK and in April 2021 released its 3rd result of the search for 0νββ, corresponding to a tonne-year of TeO2 exposure. This is the largest amount of data ever acquired with a solid state detector and the most sensitive measurement of 0νββ decay in 130Te ever conducted, with a median exclusion sensitivity of 2.8×10^25 yr. We find no evidence of 0νββ decay and set a lower bound of 2.2 ×10^25 yr at a 90% credibility interval on the 130Te half-life for this process. In this talk, we present the current status of CUORE search for 0νββ with the updated statistics of one tonne-yr. We finally give an update of the CUORE background model and the measurement of the 130Te 2νββ decay half-life, study performed using an exposure of 300.7 kg⋅yr.

Speaker: Simone Copello

EPS-HEP_2021_Latest results from the CUORE experiment_Copello.pdf

T06-T07: Combined: Top, Electroweak, QCD and Hadronic Physics: Part 1

Conveners: William Barter (Imperial College London), Zoltan Nagy (T (Phenomenology))

433 Complementarity of Lepton-Charge and Forward-Backward Drell-Yan Asymmetries for Precision Electroweak Measurements and Quark Density Determinations

Thanks to the large amount of data that is being and will be collected at Run-III and High Luminosity (HL) stage, precision measurements at the LHC are reaching an unprecedented level of statistical accuracy, whilst PDF uncertainties prevail. We study the impact of future measurements of lepton-charge and forward-backward asymmetries on PDF determination. The numerical results have been obtained employing the open-source platform xFitter and standard profiling procedures. We explore the potential of the combination of charged-current and neutral-current Drell-Yan (DY) asymmetries in regions of transverse and invariant masses near the SM gauge bosons peaks to improve the PDF uncertainties.

Speaker: Francesco Giuli (INFN and University of Tor Vergata)

Giuli_AWvsAFB_EPS21.pdf

434 Mixed QCD-EW corrections to Drell-Yan at the LHC

Drell-Yan lepton pair production is a benchmark process at hadron colliders.
From the theoretical side, the inclusion of higher-order radiative corrections is mandatory
in order to match the experimental accuracy attainable at the LHC.
QCD radiative corrections are known up to order $\alpha^3_s$ for inclusive cross
sections and up to order $\alpha^2_s$ for differential observables; EW corrections are known up to order $alpha$.
At this level of precision, the inclusion of mixed QCD-EW corrections becomes relevant.

We report on the first complete computation of the mixed QCD−EW corrections to
the neutral- and charged- current Drell−Yan processes. In the former case, the two-loop virtual contribution
is computed exactly by using semi-analytical techniques, overcoming the technical problems in the evaluation
of the relevant master integrals, and it is compared to an "improved" pole approximation, employed for the
charged-current process. The cancellation of soft and collinear singularities is
achieved by a formulation of the $q_T$-subtraction formalism valid in presence of charged massive particles
in the final state.

Superseding previously applied approximations, our calculation provides the first result at this order
that is valid in the entire range of invariant masses of the charged lepton-anti-lepton pair.

Speaker: Luca Buonocore (University of Zurich)

Mixed_Corrections_EPS.pdf

435 The impact of mixed QCD-EW corrections on the W-mass measurement

The target precision for $W$-mass measurements at the LHC is around 0.1 permille, an extremely ambitious goal that requires exceptional theoretical control on vector boson production. I will present the results of a recent calculation of the mixed QCD $\times$ EW corrections to $W$ and $Z$ boson production. I will then discuss the impact of these corrections on the measurement of the $W$ boson mass at the LHC using the transverse momentum of the charged leptons arising from the decay of the $W$ boson.

Speaker: Raoul Röntsch (CERN)

roentsch_eps.pdf

436 Impact of correlations on the PDF uncertainty in the W mass measurement

We present the results of the recent study published in Phys.Rev.Lett. 126 (2021) 4, 041801, where the PDF uncertainty affecting the MW determination at the LHC is estimated keeping into account the full correlations information from the PDF at the level of the differential distribution used to extract $M_W$, namely $p_T^l$.

We find that keeping these correlations into account can reduce significantly the PDF uncertainty (once other sources of uncertainties are under control) so that it should not represent a bottleneck in reaching the ultimate precision in the MW determination at hadron colliders.

Speaker: Emanuele Bagnaschi (Paul Scherrer Institute (CH))

EPS-2021-BAGNASCHI-MW_v3.pdf

T08: Flavour Physics and CP Violation: Part 6

Conveners: Alexander Glazov (BELLE (BELLE II Experiment)), Trabelsi Karim (BELLE (BELLE II Experiment))

437 ATLAS results on charmonium production and B_c production and decays

Recent results from the proton-proton collision data taken by the ATLAS experiment on the charmonium production and on the B_c production and decays will be presented. The measurement of J/psi and psi(2S) differential cross sections will be reported as measured on the whole Run 2 dataset. The measurement of the differential ratios of the B_c+ and B+ production cross sections at 8 TeV will also be discussed. New results on the B_c decays to J/psi Ds(*) final states obtained with the Run 2 data at 13 TeV will be shown.

Speaker: Tatiana Lyubushkina (Joint Institute for Nuclear Research)

Lyubushkina_ATLAS_QBcProd.pdf

438 ATLAS results on exotic heavy hadrons

Recent results from the ATLAS experiment on searches and measurements on exotic heavy hadrons will be presented.
Studies of the pentaquarks with hidden charm in the Lambda_b decays in proton-proton collisions at 7 - 8 TeV will be discussed.
New results on the heavy tetraquarks in the Run 2 data at 13 TeV will also be reported.

Speaker: Andy Wharton (Lancaster University)

EPS-2021.pdf

439 Recent LHCb results on CP violation in beauty decays to charmonia

The latest results of time-dependent CP Violation in beauty meson decays to charmonia from LHCb are presented, including the CP violating mixing phase phis in Bs → JpsiPhi, using for the first time Jpsi → e+e- . Updates on the measurement of branching ratios are also reported.

Speaker: Valeriia Lukashenko

LHCbB2CC_VLukashenko_EPS2021.pdf

T10: Searches for New Physics: Part 7

All talks in this session will be 12 mins + 3 mins for the discussion.

Conveners: Cristina Botta (University of Zurich), Marija Vranjes Milosavljevic (Institute of Physics Belgrade)

440 Mass Unspecific Supervised Tagging (MUST) for boosted jets

Jet identification tools are crucial for new physics searches at the LHC and at future colliders. We introduce the concept of Mass Unspecific Supervised Tagging (MUST) which relies on considering both jet mass and transverse momentum varying over wide ranges as input variables — together with jet substructure observables — of a multivariate tool. This approach not only provides a single efficient tagger for arbitrary ranges of jet mass and transverse momentum, but also an optimal solution for the mass correlation problem inherent to current taggers. By training neural networks, we build MUST-inspired generic and multi-pronged jet taggers which, when tested with various new physics signals, clearly outperform the variables commonly used by experiments to discriminate signal from background. These taggers are also efficient to spot signals for which they have not been trained. Taggers can also be built to determine, with a high degree of confidence, the prongness of a jet, which would be of utmost importance in case a new physics signal is discovered.

Speaker: João Seabra (CFTP (IST, Lisbon))

MUST_EPS-HEP2021.pdf

MUST_EPS-HEP2021.pptx

441 A Meta-Analysis of LHC Results

We report the results of a meta-analysis conducted to examine possible biases in the uncertainty values published in papers by the LHC experiments. Due to limited availability of computer readable data, we perform this analysis using custom developed python code that extracts the information from the vector graphics source files of the plots in the papers. The aim is to compute the percentages of the data points scattered within 1-sigma and 2-sigma bands of the plots and verify whether the measured percentages agree with statistical norms assuming unbiased estimations of the uncertainties.

Speaker: Ms Sevim Açıksöz (1) Boğaziçi University Department of Physics, İstanbul, Turkey 2) Turkey R&D Intelligent Application DC Department, Huawei Technologies, İstanbul, Turkey)

Atlas-Cms-Meta-Analysis_eps21.pdf

442 The Dark Machines Anomaly Score Initiative: Benchmark Data and Model Independent Classification for the Large Hadron Collider

We describe the outcome of a data challenge to detect signals of new physics at the LHC using unsupervised machine learning algorithms conducted as part of the Dark Machines Initiative and the Les Houches 2019 workshop on Physics at TeV colliders. We first define and describe a large benchmark dataset, consisting of $>1$ Billion simulated LHC events corresponding to 10 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 13 TeV. We then review a wide range of anomaly detection and density estimation algorithms, developed in the context of the data challenge, and we measure their performance in a set of realistic analysis environments. We draw a number of useful conclusions that will aid the development of unsupervised new physics searches during the third run of the LHC, and provide our benchmark dataset for future studies.

Speaker: Joe Davies (Queen Mary University of London)

eps_talk.pdf

443 Why interpretation matters for BSM searches: a case study with Heavy Neutral Leptons at ATLAS

Even the simplest consistent models of Heavy Neutral Leptons (HNLs) already feature significant complexity, making them impractical for reporting experimental results. In order to keep this complexity manageable, experiments typically interpret their results within simplified models, where e.g. one HNL couples to a single lepton flavor. Unfortunately, such models are in direct contradiction with the observed neutrino oscillation data. This can significantly reduce the impact of these results, which cannot easily be reused by model builders. In this work, we perform a detailed reinterpretation of the latest ATLAS search for prompt HNLs in W decays within a minimal low-scale seesaw with two HNLs. We show that the exclusion limits obtained using the detailed reinterpretation can differ by several orders of magnitude (in either direction) from the limits quoted for the simplified models. Hence naively comparing the mixing angles from a realistic model to the reported limits could lead to wrongly excluding entire regions of parameter space! To overcome this issue without requiring experiments to report constraints on all possible HNL models, we propose a simple framework that allows to easily and accurately reinterpret exclusion limits within closely-related models, hence significantly broadening their impact. We outline a number of concrete steps which can be taken by experiments to implement this method with minimal effort, and we discuss its applicability to other models of feebly interacting particles.

Speaker: Jean-Loup Tastet (EPFL)

JLTastet_HNL_reinterpretation.pdf

T11: Quantum Field and String Theory: Part 2

444 Black hole metamorphosis: what happens after half evaporation?

Hawking's calculation of particle production by a black hole is based on the semi-classical approximation, in which back-reaction on the metric is not taken into account. This leaves open the question of how the black hole evolves as a result of evaporation. In an attempt to answer it, we construct a simple analogue system, which shares the information storage properties of a black hole such as its Bekenstein-Hawking entropy. We find indications that at the latest after losing half of the mass, a black hole undergoes a metamorphosis leading to a drastic deviation from Hawking evaporation. As two likely possibilities for the subsequent evolution, it can either become extremely long lived or decay via a new classical instability. The first option would open up a new window for small primordial black holes as viable dark matter candidates.

Speaker: Dr Sebastian Zell (EPFL - Ecole Polytechnique Federale Lausanne (CH))

EPS21_final.pdf

445 Non-singular vortices with positive mass in 2+1-dimensional Einstein gravity with AdS$_3$ and Minkowski background

We find numerically static vortex solutions where the scalar and gauge fields have a non-singular profile under Einstein gravity in an AdS$_3$ background. Vortices with different winding numbers $n$, VEV $v$ and cosmological constant $\Lambda$ are obtained. These vortices have positive mass and are not BTZ black holes as they have no event horizon. The mass is determined in two ways: by subtracting the numerical values of two separate asymptotic metrics and via an integral that is purely over the matter fields. The mass of the vortex increases as the cosmological constant becomes more negative and this coincides with the core of the vortex becoming smaller (compressed). We then consider the vortex with gravity in asymptotically flat spacetime for different values of the coupling $\alpha=1/(16 \pi G)$. At the origin, the spacetime has its highest curvature and there is no singularity. It transitions to an asymptotic conical spacetime with angular deficit that increases significantly as $\alpha$ decreases. For comparison, we also consider the vortex without gravity in flat spacetime. For this case, one cannot obtain the mass by the first method (subtracting two metrics) but remarkably, via a limiting procedure, one can obtain an integral mass formula. In the absence of gauge fields, there is a well-known logarithmic divergence in the energy of the vortex. With gravity, we present this divergence in a new light. We show that the metric acquires a logarithmic term which is the $2+1$ dimensional realization of the Newtonian gravitational potential when General Relativity is supplemented with a scalar field.

Speaker: Ariel Edery (Bishop's University)

Edery_Vortex_EPS-HEP2021.pdf

446 The Higgs field in brane-worlds

The problematic huge hierarchy between the usual 4-dimensional Planck mass scale of gravity and the ElectroWeak symmetry breaking scale can interestingly disappear at some point-like location along extra space-like dimensions where the effective gravity scale is reduced down to the TeV scale. Field theories with point-like particle locations (3-dimensional brane-worlds) or point-like interactions deserve special care. In particular it can be shown that, in contrast with usual literature, brane-scalar fields – like the Standard Model Higgs boson – interacting with fermions in the whole space (bulk) do not need to be regularized if rigorous 4- or 5-dimensional treatments are applied: standard regularization introduces a finite width wave function for scalar fields localized along extra dimensions. The variational calculus of least action principle must also be applied strictly to derivate the fermion (Kaluza-Klein) masses and couplings, in particular by distinguishing the natural and essential boundary conditions: the higher-dimensional model – based in particular on extra compact spaces of type interval or circle (orbifold) – must be defined either completely through the action expression [necessity then for new specific brane terms bilinear in the fermion fields] or partially from additional so-called essential boundary conditions. Besides, the correct action integrand definition requires to introduce improper integrals in order to remain compatible with the fermion wave function discontinuities induced by point-like Higgs interactions. These presented new brane-Higgs treatments have phenomenological impacts and in particular the relaxing of previously obtained strong bounds on Kaluza-Klein masses, induced by flavour changing reactions generated through exchanges of the Higgs field.

Speaker: Grégory Moreau (IJCLab, Université Paris-Saclay)

G.Moreau_EPS-HEP.pdf

T12: Detector R&D and Data Handling: Future colliders

Conveners: Magnus Mager (CERN), Vincent Boudry (LLR – École polytechnique)

447 The preshower and the muon detection system of the IDEA detector for FCC-ee

The μ-RWELL is a Micro Pattern Gas Detector (MPGD) that inherits some of the best characteristics of existing MPGDs, like GEMs and MicroMegas, while simplifying the detector construction. It also significantly improves the spark protection by incorporating in the design a resistive layer on the anode board. The μ-RWELL [1] is composed of only two elements: the cathode, a simple FR4 PCB with a thin copper layer on one side and the μ-RWELL_PCB, the core of the detector. The μ-RWELL_PCB, realized as a multi-layer circuit by means of standard photo- lithography technology is composed of a well-matrix patterned on an Apical foil acting as amplification element of the detector; a resistive layer, realized with a Diamond-Like-Carbon (DLC) film sputtered on the bottom side of the polyimide foil, as discharge limitation stage; a standard PCB, segmented as strip, pixel, or pad electrodes, for readout purposes. The μ-RWELL, showing excellent spatial performance, good time resolution, and the capability to operate in harsh environments [2], is proposed in different versions in HEP experiments: as device for the upgrade of the LHCb muon system [3] and inside the IDEA detector concept, considered by both the FCC-ee [4] and the CEPC [5,6] colliders, to realize the preshower of the dual readout calorimeter as well as the full muon detection system. Key points of such a technology are the scalability and production by industrial processes which allow cost-effective mass production of the detector: a must in view of the construction, for example, of large muon systems at future HEP Colliders where huge detection surfaces (O(10000)m 2 ) are expected. I will present the R&D status with the latest results achieved and the activities planned until 2024 in terms of detector design, simulation, and test.

Speaker: Marco Poli Lener (INFN – LNF, Frascati)

PoliLener_EPS_2021_07_28.pdf

448 TPC Development by the LCTPC Collaboration for the ILD Detector at ILC

A large, worldwide community of physicists is working to realise an exceptional physics program of energy-frontier, electron-positron collisions with the International Linear Collider (ILC). The International Large Detector (ILD) is one of the proposed detector concepts at the ILC. The ILD tracking system consists of a Si vertex detector, forward tracking disks and a large volume Time Projection Chamber (TPC) embedded in a 3.5 T solenoidal field. The TPC is designed to provide 220 three dimensional points for continuous tracking with a single-hit resolution better than 100 μm in rφ, and about 1 mm in z. An extensive research and development program for a TPC has been carried out within the framework of the LCTPC collaboration. A Large Prototype TPC in a 1 T magnetic field, which allows to accommodate up to seven identical Micropattern Gaseous Detector (MPGD) readout modules of the near-final proposed design for ILD, has been built as a demonstrator at the 5 GeV electron test-beam at DESY. Three MPGD concepts are being developed for the TPC: Gas Electron Multiplier, Micromegas and GridPix. Successful test beam campaigns with different technologies have been carried out. Fundamental parameters such as transverse and longitudinal spatial resolution and drift velocity have been measured. In parallel, a new gating device based on large-aperture GEMs have been produced and studied in the laboratory. In this talk, we will review the track reconstruction performance results and summarize the next steps towards the TPC construction for the ILD detector.

Speaker: Alain Bellerive (not set)

LCTPC_EPS2021_edit.pdf

449 New ideas on detector technology for the ILC experiments

Detector concepts are being developed for the foreseen electron-positron International Linear Collider (ILC) in Japan. The detectors are being optimized for precision physics in a range of energies between 90 GeV and 1 TeV. This talk will summarize the required performance of detectors, the proposed implementation and the readiness of different technologies needed for the deployment at ILC.

Speaker: Maxim Titov (CEA Saclay, Irfu)

1_2021_07_DESY_ESPHEP2021_NEW-IDEAS-DETECTOR-TECHNOLOGIES_ILC-EXPERIMENT_28072021.pptx

450 Muon reconstruction performance and detector-design considerations for a Muon Collider

A muon collider has a great potential for particle physics giving the possibility to reach the high center-of-mass energy and luminosity of hadron colliders, with a greatly reduced pile up effect. However, a series of challenges arise mainly from the short muon lifetime and the Beam-induced Background. A complete simulation,based on CLIC’s ILCSoft software, is ongoing to understand the performance of the full detector. Concerning the muon system, the iron yoke plates are meant to be instrumented with layers of track sensitive chamber to enhance the muon identification. At the moment, according to CLIC geometry, glass Resistive Plate Chambers with readout cells of 30x30 mm$^{2}$ have been adopted both for the barrel and the endcap region. Other possible solutions,based on MicroPattern Gaseous Detectors, will be discussed considering their characteristics and performance.
The results of a preliminary study investigating the muon reconstruction efficiency, Beam-induced Background sensitivity and background mitigation are presented for muon beams collisions at a center-of-mass energy of 1.5 TeV.

Speaker: Dr Ilaria Vai (Università di Bergamo and INFN Pavia)

EPSHEP2021_IlariaVai_V2.pdf

T13 - Accelerator for HEP: Part 2

451 Preparing the ILC accelerator project - an International Pre-Lab

The International Linear Collider (ILC) is a superconducting $e^+e^-$ collider with a centre-of-mass energy of 250GeV, upgradeable in in energy to 500GeV and beyond, and in luminosity by factors of 2 to 4. At 250GeV, it will run as a Higgs factory, the worldwide top priority in future HEP projects. It will be located in the Kitakami mountains in Japan’s Tohoku (northwest) region.

In 2020, the International Development Team (ITD) hosted by KEK has been established by ICFA to plan the Preparatory Laboratory (Pre-Lab) for a start in 2022. The Pre-Lab will coordinate further R&D work of critical items and prepare the actual construction of the ILC, with a target to be ready for construction in 2026, and first physics by 2035.

After briefly recalling the ILC accelerator concept we report on the Engineering Design plans for the Pre-Lab phase, and the Technical Preparation plan, which focusses on superconducting technology and nanobeams, plus further R&D on sources, in particular the positron source, and dumps. The status of the International planning for the technical work contained within the Pre-Lab phase will be summarised.

Speaker: Benno List (IPP (Info-management Prozesse u. Projekte))

EPS-List-210728.pptx

452 A demonstrator to investigate the feasibility of a Muon Collider

Following the input of the European Strategy Update released in 2020, an International Collaboration hosted by CERN is being formed to investigate the feasibility and the physics reach of a muon collider in two stages, the first at around 3 TeV, and the second at an energy in excess of 10 TeV. The International Muon Collider Study is organised around three pillars, the design of the colliders at 3 and 10÷14 TeV, the development of prototypes and hardware test facilities for the most critical components, and finally the proposal for a beam test facility whose aim is to produce, capture and provide in a convincing way a demonstration that it is possible to provide sufficient cooling to achieve the performances required for injecting in the collider ring, and measure the cooling and transmission efficiencies. As a first step a full review of past results obtained by collaborations in the different regions is being performed. In parallel, possible options and sites for its construction are being investigated. At CERN we are developing ideas for a campus compatible with the present CERN infrastructure and future developments and that may take advantage of existing beam lines, while not interfering with already approved programs. A first decision has to be taken on the energy at which muons will be produced, which will allow to select between the PS and the SPS complex of accelerators and experimental areas. Also, it would be suitable to design a facility that could possibly evolve in the future into the final collider complex. This paper will describe the status of the discussions and the possible options at stake.

Speaker: Daniel Schulte (CERN)

EPS_TF.pdf

453 Experimental beam tests for FCC-ee

ossible circular colliders for the post-LHC era at CERN are being explored within the framework of the Future Circular Collider (FCC) feasibility study.
The first stage of the FCC integrated project is the FCC-ee, an ambitious electron-positron collider with a circumference of approximately 100 km.
Certain key concepts of the FCC-ee design can be demonstrated and tested at existing facilities, such as at SuperKEKB at KEK, DAFNE at INFN, KARA at KIT, PETRA III at DESY, VEPP-4M at BINP, and the SwissFEL at PSI. The test of a prototype positron source at PSI, understanding the crab-waist collision scheme at SuperKEKB and DAFNE, testing optics control and emittance tuning techniques at SuperKEKB and PETRA III, and precise beam energy calibration at VEPP-4M will offer invaluable insights for the FCC-ee design optimisation and its operational procedures. The results of these beam tests will be an essential input to the FCC Feasibility Study Report.
This talk will give an overview of possible experimental tests for FCC-ee and highlight already successfully performed studies.

Speaker: Jacqueline Keintzel

Keintzel_EPSHEP_20210728.pdf

T14: Outreach, Education and Diversity: Part 3

454 ALICE virtual visits and masterclasses during the COVID pandemic

With the onset of the COVID pandemic in 2020 all outreach and educational activities with in-person participation had to stop. The ALICE Collaboration adapted to the new situation and continued reaching out to the public using the multitude of online tools and platforms available. We will focus here on two of our main outreach activities, virtual visits and masterclasses.
With the cancellation of all in-person visits to the underground installations, virtual visits became the only way to explore the experiment. ALICE had already been offering virtual visits for remote audiences with equipment installed in the ALICE Run Control Centre (ARC). We recently acquired dedicated mobile equipment for the virtual visits to the cavern and developed a scenario which includes both the cavern and the ARC as well as a Q&A session. In this way, visitors from many countries have the opportunity to interact with scientists and to see parts of the experiment that they would never be able to see during a real visit.
ALICE has been participating in the International Masterclasses (IMC) programme ever since measurements based on LHC data were introduced in it. The packages used had been developed by simplifying the ALICE event display and were based on ROOT. With the spreading of the COVID pandemic the 2020 IMC programme was interrupted. In 2021, with most activities taking place remotely, it was obvious that web-based versions were needed. The implementation of such versions allowed us to hold remote masterclasses for high-school students, thus ensuring the continuity of this important outreach activity of our community. In addition we reached new countries and also involved high-school teachers in this global effort.

Speaker: Despina Hatzifotiadou (INFN Bologna)

alice-vv-mc.pdf

alice-vv-mc.pptx

455 Diversity & Inclusion in the CMS Collaboration

The CMS Collaboration is one of the largest scientific organizations ever assembled, with over 5000 active members from 229 institutes in 51 countries and regions. The goal of the CMS Diversity Office is to foster a working environment where all members of the Collaboration can thrive; ensuring the collaboration’s diverse and inclusive environment is essential for its continued success. In this presentation, we highlight some of the activities of the CMS Diversity Office and present some statistics regarding diversity and inclusion of the CMS Collaboration.

Speaker: Meenakshi Narain (Brown University)

EPS-July2021_CMS-Diversity-v2.pdf

456 Democratizing LHC data analysis with ADL/CutLang

Data analysis at the LHC has a very steep learning curve, which erects a formidable barrier between data and anyone who wants to analyze data, either to study an idea or to simply understand how data analysis is performed. To make analysis more accessible, we designed the so-called Analysis Description Language (ADL), a domain specific language capable of describing the contents of an LHC analysis in a standard and unambiguous way, independent of any computing frameworks. ADL has an English-like highly human-readable syntax and directly employs concepts relevant to HEP. Therefore it eliminates the need to learn complex analysis frameworks written based on general purpose languages such as C++ or Python, and shifts the focus directly to physics. Analyses written in ADL can be run on data using a runtime interpreter called CutLang, without the necessity of programming. ADL and CutLang are designed for use by anyone with an interest in, and/or knowledge of LHC physics, ranging from experimentalists and phenomenologists to non-professional enthusiasts. ADL/CutLang are originally designed for research, but are also equally intended for education and public use. This approach has already been employed to train undergraduate students with no programming exprience in LHC analysis in two dedicated schools in Turkey and Vietnam, and is being adapted for use with LHC Open Data. Moreover, work is in progress towards piloting an educational module in particle physics data analysis for high school students and teachers. In this talk, we will introduce ADL and CutLang and present the educational activities based on these practical tools.

Speaker: Sezen Sekmen (Kyungpook National University (KR))

SekmenADLEPSHEP2107.pdf

ÖFFENTLICHER ABENDVORTRAG (auf Deutsch / in German)

Conveners: Johannes Haller (Institut für Experimentalphysik, Universität Hamburg), Ties Behnke (FLC (Forschung an Lepton Collidern))

457 Auf der Suche nach der mysteriösen Dunklen Materie

Zoom webinar

Im Universum muss es 6-mal mehr Materie geben, als die uns bekannte aus Atomen aufgebaute Materie, besagen einhellig alle astrophysikalischen und kosmologischen Messungen: Über 80% der Materie im Universum ist eine uns unbekannte neue Form von Materie, die wir "Dunke Materie" nennen. So ist unsere Galaxie, die Milchstraße, von einem Halo aus Dunkler Materie umgeben. Aus was besteht dann diese Dunkle Materie, wenn nicht aus Atomen?

Die Physiker*innen vermuten, dass es sich dabei um eine neue Art von Elementarteilchen handelt, für die sie mehrere Ideen haben. Weltweit wird mit verschiedenen Techniken nach Signaturen dieser Teilchen gesucht, so auch mit dem ALPS-Experiment am DESY oder mit Experimenten am LHC-Collider am europäischen Teilchenphysikzentrum CERN. Das XENON-Experiment im italienischen Untergrundlabor LNGS 1500m tief unter der Erde will die Dunkle Materie in unserer Milchstraße direkt messen: Es führt eine extrem empfindliche Suche nach der Streuung der Dunkle Materie Teilchen mit Atomen des Edelgases Xenon durch.

Der Vortrag erklärt, welche Messergebnisse die Evidenz für Dunkle Materie belegen, und wie wir mit den Methoden der
(Astro-)Teilchenphysik mit sehr raffinierten Experimenten danach suchen.

Speaker: Christian Weinheimer (University of Muenster, Institut für Kernphysik)

Live Stream Recoring [YouTube]

Thursday, 29 July

T01: Astroparticle and Gravitational Waves: Part 7

458 Neutrino Telescope in Lake Baikal: Present and Nearest Future

The progress in the construction and operation of the Baikal Gigaton Volume Detector in Lake Baikal is reported. The detector is designed for search for high energy neutrinos whose sources are not yet reliably identified. It currently includes over 2300 optical modules arranged on 64 strings, providing an effective volume of 0.4 km3 for cascades with energy above 100 TeV. We review the construction plan and first results from the partially built detector which is currently the largest neutrino telescope in the Northern Hemisphere and still growing up.

Speaker: Lukáš Fajt (IEAP CTU in Prague)

baikal-gvd_eps-hep_fajt.pdf

459 PLEnuM: A global and distributed monitoring system of high-energy astrophysical neutrinos

High-energy astrophysical neutrinos, discovered by IceCube, are now regularly observed.
Due to their low flux the observation rate remains small, such that open questions about high-energy neutrino astrophysics and particle physics remain limited by statistics at best, or unanswered at worst. Fortunately, this situation will improve in the next years: new neutrino telescopes will come online, which are currently under planning and construction. In order to answer open questions, we propose the Planetary Neutrino Monitoring System (PLEnuM), a concept for a global repository of high-energy neutrino observations. PLEnuM will reach up to four times the exposure available today by combining the exposures of current and future neutrino telescopes distributed around the world − IceCube, IceCube-Gen2, Baikal-GVD, KM3NeT, and P-ONE. Depending on the declination, spectral index and flavor, PLEnuM will improve the sensitivity to astrophysical neutrinos by up to two orders of magnitude. We present first estimates on the capability of PLEnuM to discover Galactic and extragalactic sources of astrophysical neutrinos and to characterize the diffuse flux of high-energy neutrinos in unprecedented detail.

Speaker: Lisa Schumacher (TU Munich)

20210729_lschumacher_plenum_EPS-HEP.pdf

460 Neutrino emission from temporarily-absorbed gamma-ray blazars

Since the discovery of high-energy neutrinos by the IceCube South Pole Neutrino Detector in 2013, the origin of their cosmic flux is still under debate. Every piece of the puzzle that helps to understand their acceleration sites is of great interest, because cosmic neutrinos are key messengers to explore the non-thermal universe where it is opaque to the cosmic rays and photons. IceCube recorded its highest-energy cosmic neutrino alert ever on 2019 July 30, IC-190730A, which quickly became associated with the blazar PKS 1502+106. By analyzing multimessenger observations on this source, we point out that a scenario, in which gamma-ray emission is suppressed during efficient neutrino production, could potentially resolve the apparent contradiction of the blazar models simultaneously producing a detectable neutrino flux and a gamma flare, since at the time of efficient neutrino production the observed gamma-flux drops. We show other examples of possible gamma suppression, TXS 0506+056 and PKS B1424-418. Temporary gamma-suppression could increase the sensitivity of neutrino-blazar coincidence searches due to the short allowed time coincidence between gamma-suppressed periods and neutrinos, enabling the identification of the origin of IceCube’s diffuse neutrino flux possibly with already existing data.

Speaker: Emma Kun (Konkoly Observatory)

EPS-HEP-NuGamma_Talk_EK.pdf

10:30 Coffee Break

461 Results from the LHCf Run II in proton-proton collisions at √s = 13 TeV

The LHCf experiment, at the Large Hadron Collider (LHC), consists of two small independent calorimeters placed 140 metres away, on opposite sides of the ATLAS interaction point (IP1). LHCf has the capability to measure zero-degree neutral particles, covering the pseudorapidity region above 8.4. By measuring the very-forward particle production rates at the highest energy possible at an accelerator, LHCf aims to improve our understanding of hadronic interactions in air-showers induced by ultra-high-energy cosmic rays in the atmosphere.
This contribution will highlight recent results from Run II measurements with p-p collisions at 13 TeV. First, I will show our neutron energy spectrum measurements, for several pseudorapidity regions, and compare them to the predictions of various hadronic interaction models. From these measurements, we have also extracted the average inelasticity of the collisions, which strongly affects the development of an air-shower. I will then present our $π^0$ Feynman-x and transverse momentum spectra, which affect the development of the electromagnetic component of an air-shower, and also compare them to model predictions. Finally, I will discuss the advantages of an ATLAS-LHCf combined analysis, and show a preliminary energy spectrum of very-forward photons produced in diffractive collisions as tagged by ATLAS.

Speaker: Alessio Tiberio (INFN, Firenze (IT))

tiberio_EPS-HEP_2021.pdf

462 High Energy Physics Astroparticle Experiments to Improve the Radiation Health Risk Assessment in Space Missions

In the near future all the space agencies are working to restart the human exploration of the space outside the Low Earth Orbit (LEO). Manned space missions in this and the next decade will see the presence of humans on the Moon and Mars surface. One of the main showstopper to be investigated for a safe exploration and colonization is the ionizing radiation biological effects that can compromise the health of astronauts/space-workers.
In this important task a principal roles could and do be done by the astroparticle experiments presently operating in space. Such experiments are a source of information crucial to improve the knowledge of radiobiology effects in space. In this talk a review of the past and present astroparticle experiments will be presented and will be highlighted some of the possible contributions and improvements in the space radiobiology research field.

Speaker: Alessandro Bartoloni (INFN Roma & CERN)

EPS-HEP 2021AB_final.pdf

463 Latest results from DAMPE

DArk Matter Particle Explorer (DAMPE) satellite mission is successfully operating and delivering data for more than 5 years since its launch in December 2015. The instrument is a thick calorimeter type detector, targeted at measuring gamma rays and cosmic-ray electrons up to about 10 TeV with excellent energy resolution and cosmic ray ions up to 100 TeV. Precise measurements of electron, proton, and helium cosmic ray spectra have been performed by the collaboration, which is expected to bring new insights into the physics mechanisms behind cosmic rays. In this talk, we give an overview of a mission status and present the latest physics results and data analysis activities.

Speaker: Prof. Andrii Tykhonov (University of Geneva)

EPS-HEP2021__Tykhonov__DAMPE.pdf

T03: Dark Matter: Part 6

Convener: M. Patrick Decowski (Nikhef and the University of Amsterdam)

464 Axion-Photon Conversion in Magnetospheres: The Role of the Plasma

The most promising indirect search for the existence of axion dark matter uses radio telescopes to look for narrow spectral lines generated in the magnetospheres of neutron stars. Unfortunately, a large list of theoretical uncertainties has prevented this search strategy from being accepted as robust. In this talk I will present a novel end-to-end pipeline that traces individual photon trajectories from their point of genesis in the magnetosphere to asymptotic distances. This method allows one assess many of the outstanding uncertainties, including: (1) do refraction and reflection induce strong inhomogeneous features in the flux, (2) can refraction induce premature axion-photon de-phasing, (3) what is the expected width of the line, (4) does the flux have a strong time-dependence, and (5) can these radio photons be efficiently absorbed.

Speaker: Samuel Witte (GRAPPA, U. of Amsterdam)

Witte,Samuel_pdf.pdf

465 An even lighter QCD axion

We explore whether the axion which solves the strong CP problem can naturally be much lighter than the canonical QCD axion. The Z_N symmetry proposed by Hook, with N mirror and degenerate worlds coexisting in Nature and linked by the axion field, is considered and the associated phenomenology is studied in detail.
On a second step, we show that dark matter can be accounted for by this extremely light axion. This includes the first proposal of a “fuzzy dark matter” QCD axion. A novel misalignment mechanism occurs – trapped
misalignment– due to the peculiar temperature dependence of the Z_N axion potential, which in some cases can also dynamically source the recently proposed kinetic misalignment mechanism.
The resulting universal enhancement of all axion interactions relative to those of the canonical QCD axion has a strong impact on the prospects of ALP experiments such as ALPS II, IAXO and many others. For instance, even Phase I of Casper Electric could discover this axion.
Based on 2102.00012 and 2102.01082.

Speaker: Pablo Quilez Lasanta (DESY)

[EPS-HEP 21] An even lighter QCD axion.pdf

466 Photophilic hadronic axion from heavy magnetic monopoles

We propose a model for the QCD axion which is realized through a coupling of the Peccei-Quinn scalar field to magnetically charged fermions at high energies. We show that the axion of this model solves the strong CP problem and then integrate out heavy magnetic monopoles using the Schwinger proper time method. We find that the model discussed yields axion couplings to the Standard Model which are drastically different from the ones calculated within the KSVZ/DFSZ-type models, so that large part of the corresponding parameter space can be probed by various projected experiments. Moreover, the axion we introduce is consistent with the astrophysical hints suggested both by anomalous TeV-transparency of the Universe and by excessive cooling of horizontal branch stars in globular clusters. We argue that the leading term for the cosmic axion abundance is not changed compared to the conventional pre-inflationary QCD axion case for axion decay constant $f_a > 10^{12}~\text{GeV}$.

Speaker: Anton Sokolov (DESY)

Sokolov_EPS-HEP.pdf

467 Search for Axion Dark Matter with the QUAX Haloscopes

The axion, a pseudoscalar particle originally introduced to solve the "strong CP problem", is a well motivated dark-matter candidate with a mass lying in a broad range from peV to few meV. Axions clustered inside our galaxy may be observed by means of detectors called Haloscopes consisting in a resonant cavity immersed in a static magnetic field that triggers the axion conversion to microwave photons. The QUAX collaboration has put one Haloscope into operation and is installing a second one in the two national INFN laboratories in Legnaro and Frascati, respectively. The first one recently reached the sensitivity to QCD axions with masses around 40 micro-eV. Meanwhile, a rich R&D program is ongoing to improve the detectors sensitivity with superconducting and dielectric resonant-cavities and quantum devices and to extend the axion search beyond the axion-photon interaction with a "ferromagnetic" Haloscope that exploits the coupling of axions to electrons.

Speaker: Claudio Gatti (INFN)

EPS-HEP-2021-ClaudioGatti.pdf

EPS-HEP-2021-ClaudioGatti.pptx

468 Operations and Data Taking Status of ADMX

The axion is a hypothetical particle arising from the Pecce-Quinn solution to the Strong CP problem, and an excellent candidate for dark matter. The Axion Dark Matter Experiment (ADMX) is an experiment that searches for axions as a dark matter with a resonant cavity under a strong superconducting magnetic field. In previous operations, ADMX achieved sensitivity to the GUT-inspired DFSZ axion model between 2.66-3.31 eV with yocto Watt level background using a quantum amplifier and dilution refrigerator. The latest run has been in data-taking since 2020. In this run, we have improved our blind axion signal injection, improved our operating efficiency, and have new methods to distinguish true axion signals from the background. I will discuss these advances as well as the current data-taking status.

Speaker: Tatsumi Nitta

ADMX_EPS_Jul29.pdf

469 Towards New Particle Discoveries: the ALPS-II Experiment Shines Soon*

The version II of the Any Light Particle Search (ALPS) experiment is projected to be one of the most sensitive experiments for axion-like particles. Such particles are a solution to the strong CP problem in quantum chromodynamics (QCD) as well as potential dark matter candidates. Based on theory, the axion-like particles are weakly interacting with matter, making them invisible to regular detectors. However, and fortunately, these “invisible” particles are predicted to be coupled with light, with a certain conversion probability, in the presence of a strong magnetic field. This prediction opened up a way for a potential detection of these particles via optics. ALPS is a light shining through a wall (LSW) experiment where the production of the axion-like particles would be occurring in a pure laboratory setting: a high power laser will shine through a string of 12 superconducting HERA dipole magnets, located in the HERA tunnel at DESY in Hamburg, Germany. At the end of these magnets, a “wall” will block the laser light while the axion-like particles would pass through it towards a second similar set of 12 HERA magnets, which would regenerate a tiny amount of the axion-like particles back to detectable photons. Also, by implementing two high finesse 124 m baseline Fabry-Perot cavities at the production and regeneration sides, ALPS-II could increase its upper limit sensitivity in the coupling factor between the axion-like particles and the photons down to $g_{a\gamma\gamma}=2\times10^{-11}\text{GeV}^{-1}$. I will report on the optics commissioning status and its stages which started at the beginning of this year, on the latest milestones that we have reached, and finally on the science runs and results that we are expecting from our experiment.

*We acknowledge the support of the National Science Foundation (Grant No. 1802006), of the Heising-Simons Foundation (Grant No. 2015-154 and 2020-1841).

Speaker: Ayman Hallal (ALPS (ALPS _ Any Light Particle Search))

EPS_HEP_Conference_2021_Ayman Hallal.pdf

T04: Neutrino Physics: Atmospheric and astrophysical neutrinos

Convener: Pilar Coloma (Instituto de Fisica Teorica UAM/CSIC)

470 Probing the Earth's Core using Atmospheric Neutrinos at INO

The Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) aims to detect atmospheric neutrinos and antineutrinos separately in the multi-GeV range of energies and over a wide range of baselines. By utilizing its charge identification capability, ICAL can efficiently distinguish $\mu^-$ and $\mu^+$ events. Atmospheric neutrinos passing long distances through Earth can be detected at ICAL with good resolution in energy and direction, which enables ICAL to see the density-dependent matter oscillations experienced by upward-going neutrinos in the multi-GeV range of energies. In this work, we explore the possibility of utilizing neutrino oscillations in the presence of matter to extract information about the internal structure of Earth complementary to seismic studies. Using good directional resolution, ICAL would be able to observe 331 $\mu^-$ and 146 $\mu^+$ core-passing events with 500 kt$\cdot$yr exposure. With this exposure, we show for the first time that the presence of Earth's core can be independently confirmed at ICAL with a median $\Delta \chi^2$ of 7.45 (4.83) assuming normal (inverted) mass ordering by ruling out the simple two-layered mantle-crust profile in theory while generating the prospective data with the PREM profile.

Speaker: Prof. Sanjib Kumar Agarwalla (Institute of Physics, Bhubaneswar, Odisha)

Sanjib-EPS-HEP-2021.pdf

471 KM3NeT/ORCA overview

KM3NeT is the Mediterranean distributed deep-sea research infrastructure, hosting the next-generation Cherenkov detectors for the observation and study of neutrinos in the energy range from few GeV up to few PeV. KM3NeT/ORCA (Oscillations Research with Cosmics in the Abyss), the detector aimed at the study of low energy neutrinos (> 1 GeV), is currently under construction off the coast of Toulon in France, at a depth of about 2500 m. In its final configuration, ORCA will include 2070 digital optical modules (DOM) distributed over 115 detection lines. Each DOM contains 31 photomultiplier tubes with a diameter of 3”. This megaton-size detector is optimized for studies of atmospheric neutrino oscillations, with the primary goal to determine the neutrino mass ordering. Other measurements planned with ORCA include searches for sterile neutrinos, non-standard interactions, and neutrino oscillation tomography of the Earth.
Currently the configuration with 6 deployed lines (ORCA6) is steadily taking data. The status, current performance, and prospects of the KM3NeT ORCA project will be discussed in the talk.

Speaker: Revaz Shanidze (Tbilisi State University)

Shanidze_KM3NeT_ORCA_Overview_EPS_HEP2021.pdf

472 The future of high-energy astrophysical neutrino flavor measurements

The high-energy cosmic neutrinos seen by IceCube allow us to perform new, powerful tests of high-energy particle physics and astrophysics. In particular, there is vast potential to perform these tests using the high-energy flavor composition, i.e., the proportion of electron, muon, and tau neutrinos in the high-energy neutrino flux. However, presently, these tests are limited by uncertainties in the measurement of flavor in neutrino telescopes and of the neutrino mixing parameters in oscillation experiments. Fortunately, these limitations will be overcome in the next two decades, thanks to new neutrino telescopes---IceCube-Gen2, KM3NeT, Baikal GVD, P-ONE, TAMBO---and new oscillation experiments---JUNO, DUNE, Hyper-Kamiokande. Based on detailed projections of their performance, I will show that in the 2030s flavor will finally become a precision tool for high-energy neutrino physics and astrophysics. I will showcase two examples: inferring the astrophysical neutrino production mechanism and placing stronger constraints on the neutrino lifetime.

Speaker: Mauricio Bustamante (Niels Bohr Institute)

2021-07-29-Bustamante-EPS-HEP.pdf

2021-07-29-Bustamante-EPS-HEP.pdf

473 Probing Dark Matter Models with Upcoming Neutrino Telescopes

Next generation of neutrino telescopes currently under construction are drastically improving their ability to constrain the annihilation cross-section of dark matter. In this talk after introducing an angular power spectrum analysis method for future sensitivity of a KM3NeT-like neutrino telescope, we will discuss the implications of results on the various particle dark matter models. Particular attention will be made on the assessment of limits complementing the current direct dark matter detection and gamma ray searches. We will emphasise that future neutrino telescopes will be able to competitively probe significant portions of parameter space and therefore will provide critical complementary information on the dark matter searches.

Speaker: Suzan Basegmez du Pree (Nikhef)

Suzan_EPS-HEP_2021July29.pdf

474 On the Tau flavor of the cosmic neutrino flux

Observation of high energy cosmic neutrinos by ICECUBE has ushered in a new era in exploring both cosmos and new physics beyond the Standard Model (SM). In the standard picture, although mostly $\nu_\mu$ and $\nu_e$ are produced in the source, oscillation will produce $\nu_\tau$ {\it en route}. Certain beyond SM scenarios, like interaction with ultralight DM can alter this picture. Thus, the flavor composition of the cosmic neutrino flux can open up the possibility of exploring certain beyond the SM scenarios that are inaccessible otherwise. We show that the $\tau$ flavor holds a special place among the neutrino flavors in elucidating new physics. Interpreting the two anomalous events observed by ANITA as $\nu_\tau$ events makes the tau flavor even more intriguing. We study how the detection of the two tau events by ICECUBE constrains the interaction of the neutrinos with ultralight dark matter and discuss the implications of this interaction for even higher energy cosmic neutrinos detectable by future radio telescopes such as ARA, ARIANNA and GRAND. We also revisit the $3+1$ neutrino scheme as a solution to the two anomalous ANITA events and clarify a misconception that exists in the literature about the evolution of high energy neutrinos in matter within the $3+1$ scheme with a possibility of scattering off nuclei.
We show that the existing bounds on the flux of $\nu_\tau$ with energy of EeV rules out this solution for the ANITA events. We show that the $3+1$ solution can be saved from both this bound and from the bound on the extra relativistic degrees of freedom in the early universe by turning on the interaction of neutrinos with ultralight dark matter.

Speaker: Yasaman Farzan (IPM)

eps2021.pdf

475 Visible Decay of Astrophysical Neutrinos at IceCube

Neutrino decay modifies neutrino propagation in a unique way; not only is there flavor changing as there is in neutrino oscillations, there is also energy transport from initial to final neutrinos. The most sensitive direct probe of neutrino decay is currently IceCube which can measure the energy and flavor of neutrinos traveling over extragalactic distances. For the first time, we calculate the flavor transition probability for the cases of visible and invisible neutrino decay, including the effects of the expansion of the Universe, and consider the implications for IceCube. As an example, we demonstrate how neutrino decay addresses a tension in the IceCube data.

Speaker: Peter Denton (Brookhaven National Lab)

Denton_Neutrino_Decay.pdf

T06: QCD and Hadronic Physics: Part 7: Exotica

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Daniel Johnson (CERN)

476 Recent LHCb results on exotic meson candidates (12'+3')

Many mesons with additional valence constituents with respect to the conventional quark-antiquark pair have been discovered in the last decades, leading to a renaissance of hadron spectroscopy. Interpretations of such states span from compact objects to hadronic molecules and searches for new exotic meson candidates provide important insights on the quarks binding mechanisms inside hadrons. In this talk the recent LHCb results on this topic are presented.

Speaker: Ivan Polyakov (Syracuse University)

EPS-HEP_2021_Polyakov_v5.pdf

477 Light meson spectroscopy at BESIII (12'+3')

Due to the high production of light mesons J/ψ radiative and hadronic decays, the largest sample of J/ψ events accumulated at the BESIII detector offers a unique laboratory to study the light mesons spectroscopy and search for the light exotic states. In this talk, we shall report the recent progresses on the light meson spectroscopy achieved at BESIII.

Speaker: Jinfei Wu

EPS-lightmesonBESIII_wujf_0729.pdf

478 Production of fully heavy tetraquarks in proton-proton collisions (12'+3')

We discuss the production mechanism of a new state, a fully charm tetraquark, discovered recently by the LHCb at M = 6.9 GeV in the $J/\psi J/\psi$ channel. Both single parton scattering (SPS) and double parton scattering (DPS) mechanisms are considered. We calculate the distribution in the invariant mass of the four-quark system $M_{4c}$ for SPS and DPS production of $c c \bar c \bar c$ in the $k_t$-factorization approach with modern unintegrated gluon distribution functions (UGDFs). The so-calculated contribution of DPS is almost two orders of magnitude larger than the SPS one, but the tetraquark formation mechanism is unknown at present. We construct a simple coalescence model of the tetraquark out of $c \bar c \bar c$ continuum. Imposing a mass window around the resonance position we calculate the corresponding distribution in $p_{t,4c}$ -- the potential tetraquark transverse momentum. The cross section for the $J/\psi J/\psi$ continuum is calculated in addition, again including SPS (box diagrams) and DPS contributions which are of similar size. The formation probability is estimated trying to reproduce the LHCb signal-to-background ratio. The calculation of the SPS $g g \to T_{4c}(6900)$ fusion mechanism is performed in the $k_T$-factorization approach assuming different spin scenarios ($0^+$, $0^-$ and $2^+$). The $2^+$ and $0^+$ assignment is preferred over the $0^-$ one by a comparison of the transverse momentum distribution of signal and background with the LHCb preliminary data assuming the SPS mechanism dominance. There is no microscopic approach for the DPS formation mechanism of tetraquarks at present as this is a complicated multi-body problem.

We do similar analysis for FCC energy $\sqrt{s}$ = 100 TeV. We predict the production cross section order of magnitude larger than its counterpart for the LHC. We discuss also a possibility to observe the $T_{4c}$ state in the $\gamma \gamma$ channel. The signal-to-background ratio is estimated.

We discuss also production of $c \bar c b \bar b$ tetraquarks and discuss how the results depend on the mass of such an object.

First part of the presentation will be based on our recent paper:

R. Maciu{\l}a, W. Sch\"afer and A. Szczurek,
``On the mechanism of $T_{4c}(6900)$ tetraquark production'',
Phys. Lett. B812 (2021) 136010.

Speaker: Antoni Szczurek (Institute of Nuclear Physics PAN, Krakow and Rzeszow University, Rzeszow)

szczurek_eps2021.pdf

479 Recent LHCb results on pentaquark candidates (12'+3')

The LHCb experiment reported the first observation of pentaquark candidates in 2015, opening a new era in hadron spectroscopy. Since then, other pentaquark candidates, either with hidden-charm or charm-strange quarks content, have been reported by the LHCb collaboration. This talk presents the recent results on pentaquark spectroscopy at LHCb.

Speaker: Jinlin Fu (University of Chinese Academy of Sciences)

epshep2021_Jinlin.pdf

480 Study of phi(2170) at BESIII (12'+3')

In e+e- collisions between 2 and 3 GeV, excited states of rho, omega and phi can be produced directly. Especially the resonances around 2GeV like rho(2000), rho(2150) and \phi(2170) are not fully understood yet. Theorists describe the phi(2170) as a traditional s s-bar state, an s s-bar g hybrid, a tetraquark state, a Lambda Lambda-bar bound state, or a phi KK resonance. The predicted decay widths vary strongly depending on the assumed nature of phi(2170). With energy scan data collected by the BESIII collaboration between 2.0 GeV and 3.08 GeV, the properties of phi(2170) are studied systematically in PWAs of its expected decay modes, such as e+e- -> K+K-pi0pi0, phi eta', phi eta, K+K-, and eta' pi+pi-.

Speaker: Dong Liu (HIM, GSI, USTC)

2021-07-29-EPSHEP2021-LiuDong-phi2170.pdf

481 Studies of charmonium-like states at Belle II (12'+3')

The Belle II experiment has accumulated data corresponding to 89.99 fb-1 integrated luminosity in the past 2 years, and is performing very good. Waiting that the full planned data set will be recorded (50 ab-1), which will allow search for rare processes and will have a tremendous impact in the spectroscopy field, the Phase 3 data set allows to already perform analysis with high precision. We present here the analysis of B -> K J/psi pi pi and B -> K psi(2S): in the former for the first time the evidence for the X(3872) --->Jpsi pi pi has been found at Belle II, which is consistent with the observation at Belle of the same resonant state, performed in 2003.
The re-discovery of the X(3872) based on the early Phase3 data includes the efficiency and resolution study, calibration with B -> K psi(2S), and background check. When higher statistics will be available, Belle II is planning the even more interesting analysis of B--->DDK, and search for X(3872)→DD

Speaker: Rashmi Dhamija (IIT Hyderabad)

rashmi-EPS-HEP-2021.07.29.pdf

482 Study of e+e- annihilation to hadrons with SND at VEPP-2000 (12'+3')

Recent result on $e^+e^−$ annihilation to hadrons below 2 GeV obtained at the SND experiment at the VEPP-2000 collider are presented. In particular, we discuss measurements of the $e^+e^-\to\pi^+\pi^-$ and $e^+e^-\to n\bar{n}$ cross sections, and study of the radiative processes $e^+e^-\to \eta\gamma$, $e^+e^-\to \eta\pi^0\gamma$, and $e^+e^-\to \eta\eta\gamma$.

Speaker: Vladimir Druzhinin (BINP, Novosibirsk)

snd-epshep-2021.pdf

483 Recent study about XYZ particles at BESIII (12'+3')

In this talk recent XYZ results at BESIII will be reviewed, that includes: Observation of a near-threshold enhancement in the Lambda Lambda-bar mass spectrum from e+ e- -> phi Lambda Lambda-bar at the center-of-mass energies from 3.51 to 4.60 GeV; Observation of e+ e- -> eta psi(2S) at the center-of-mass energies from 4.236 to 4.600 GeV; Cross section measurement of e+ e- -> p pbar eta and e+ e- -> p pbar omega at center-of-mass energies between 3.773 GeV and 4.6 GeV; Search for reaction e+ e- -> chi_cJ pi+ pi- and a charmonium-like structure decaying to chi_cJ pi+/- between 4.18 and 4.60 GeV; Search for the reaction channel e+ e- -> eta_c eta pi+ pi- at center-of-mass energies from 4.23 to 4.60 GeV.

Speaker: Johannes Bloms

Talk_EPS.pdf

T07: Top and Electroweak Physics: Part 4

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Alexander Grohsjean (CMS (CMS Fachgruppe TOP)), Francesco Spanò (Royal Holloway University of London)

484 Combining ATLAS and CMS measurements of top quark production and W boson polarisation for LHC pp collisions at sqrt{s} = 7 and 8 TeV

Measurements of the inclusive top-quark pair production cross section and of the W boson polarisation in top quark decays are presented. The most precise results performedd by the ATLAS and CMS collaborations using all the proton-proton collisions data produced at the LHC at center-of-mass energies of 7 and 8 Te. The combined results provide both lower uncertainties than the individual measurements and stringent comparisons with the standard model predictions at NNLO in perturbative QCD.

Speaker: Veronique Boisvert

VBWPolEPS2021.pdf

485 Recent measurements of the top-quark mass and Yukawa coupling using the ATLAS and CMS detector at the LHC

The top quark mass is one of the fundamental parameters of the Standard Model that must be determined experimentally. Single measurements of the top quark mass have reached a precision well below the %-level. Different methods - based on a direct reconstruction of the top quark decay or an extraction from (differential) top quark production cross sections - provide complementary handles on the experimental systematic uncertainties. An overview is given of the most recent ATLAS and CMS measurements of the top -quark mass, its running and of the top quark Yukawa coupling.

Speaker: Matteo Negrini

epshep2021_negrini.pdf

486 Measurement of top-quark properties with the ATLAS and CMS detectors at LHC

The remarkably large integrated luminosity collected by the ATLAS and CMS detectors at the highest proton-proton collision energy provided by LHC allows to use the large sample of top quark events to explore properties of the top quark production and decay and to probe the presence on new physics that might break well established symmetries. The angular properties are explored by illustrating the simultaneous measurement of the all three components of the top-quark and antiquark polarisation vectors in t-channel single-top-quark production, the measurement of normalised differential cross sections for single-top t-channel production as a function of the direction cosines of the momentum of the charged lepton in the top quark rest frame, the measurement of the helicity of the W boson from the top decays . The angular differential cross sections in single-top t-channel events are used to extract the complex Wilson coefficient of the dimension-six O_{tW} operator in the framework of an effective field theory. Measurements of the top sector of the CKM matrix and of the ttbar forward backward asymmetry enrich the exploration of top quark decay and production. Finally a measurement that tests the universality of the couplings of the different generations of leptons to the electroweak gauge bosons is illustrated.

Speaker: Carlos Escobar Ibáñez (Instituto de Fisica Corpuscular (IFIC) - CSIC/UV)

Carlos Escobar - EPS-HEP2021.pdf

487 Results on Rare and BSM top quark interactions from ATLAS and CMS

The remarkably large integrated luminosity collected by the ATLAS and CMS detector at the highest proton-proton collision energy provided by LHC allows to probe the presence of new physics that might enhance extremely rare processes in the SM. Examples of such studies are presented using data collected in Run2 pp collisions at a center-of-mass of 13 TeV. These involve direct searches for top quark anomalous couplings (altered tWb vertex), Flavour Changing Neutral Currents (FCNC) like interactions between a top quark and an up- or c-quark mediated by either a Z or a gluon , as well as CP violating interactions.

Speaker: Reza Goldouzian

Reza_EPS.pdf

488 Parton shower effects in ttW @ NLO

We will present our recent calculation of matching NLO QCD corrections
to the production of a top-quark pair in association with a W boson
using the POWHEG-BOX framework. We compare our results with other
Monte Carlo generators for the two same-sign lepton signature
commonly used by the experiments. Special focus will be put on the
assessment of the importance of subleading electroweak contributions
in the modelling of the production process. In addition, We will discuss
theoretical uncertainties of our predictions, which are estimated by
variations of the renormalization and factorization scales, also
matching uncertainties are estimated.

Speaker: Manfred Kraus (Florida State University)

Mkraus.pdf

489 Associated production of tt and heavy flavor at CMS

A comprehensive set of inclusive and differential measurements of top quark pair production in association with light, c- and b-jets is presented and results are compared to theory predictions. The status of the search for four top quark production, to which the LHC experiments are starting to be sensitive, and that has important BSM re-interpretations, is also reported.

Speaker: Fabio Iemmi (Institute of High Energy Physics (IHEP))

tt_plus_HF_at_CMS.pdf

T08: Flavour Physics and CP Violation: Part 7

Conveners: Nuno Leonardo (LIP & IST), Shikma Bressler (Weizmann Institute of Science)

490 Muon $g−2$ and $\Delta\alpha$ connection

The Muon $g-2$ experiment at Fermilab has recently confirmed Brookhaven's earlier measurement of the muon anomalous magnetic moment $a_\mu$. This new result increases the discrepancy $\Delta a_\mu$ with the Standard Model (SM) prediction and strengthens its "new physics" interpretation as well as the quest for its underlying origin. Following the presentations of the new experimental result and the SM prediction of the Muon $g-2$ at this conference, I will focus on some of the latest developments and discuss the connection of the discrepancy $\Delta a_\mu$ to precision electroweak predictions via their common dependence on hadronic vacuum polarization effects. This is particularly relevant for the ongoing comparison between results for hadronic vacuum polarization effect as calculated from hadronic cross section data and from lattice QCD.

Speaker: Alex Keshavarzi (University of Manchester)

AKeshavarzi_EPSHEP_29-07-21-compressed.pdf

491 Probing New Physics with heavy hadron decays

The observations of anomalies in exclusive decays of beauty mesons, with
hints toward possible violation of lepton flavour universality, require new analyses of related processes involving other heavy hadrons, to enlarge the set of observables suitable to test the Standard Model (SM) predictions.
I will present results obtained in the study of decay modes of several hadrons containing a heavy quark.

Speaker: Fulvia De Fazio (INFN Bari)

defazio.pdf

492 New measurement of radiative decays $K^{+} \to e^{+}\nu\gamma$ and $K^{+} \to \pi^{0}e^{+}\nu\gamma$ at the NA62 experiment

The NA62 experiment at CERN reports new results from studies of radiative kaon decays 𝐾+→𝑒+𝜈𝛾 (𝐾𝑒2𝛾) and 𝐾+→𝜋0𝑒+𝜈𝛾 (𝐾𝑒3𝛾), using a data sample recorded in 2017--2018. The sample comprises O(10k) 𝐾𝑒2𝛾 candidates and O(100k) 𝐾𝑒3𝛾 candidates with sub-percent background contaminations. Preliminary results with the most precise measurement of the 𝐾𝑒2𝛾 and 𝐾𝑒3𝛾 branching ratios, determination of structure-dependent 𝐾𝑒2𝛾 form factors, and T-asymmetry measurement in the 𝐾𝑒3𝛾 decay, are presented.

Speaker: Francesco Brizioli (INFN Perugia)

EPS-HEP-2021_Brizioli_NA62_Ke3g.pdf

493 Search for rare electroweak decay $B^{+} \to K^{+}νν$ in early Belle II dataset

In the recent years, several measurements of $B$-decays with flavor changing neutral currents (FCNC), i.e. $b\to s \ell \ell$ transitions, hint at deviations from the Standard Model (SM) predictions.

A search for the flavor-changing neutral current decay $B^{+}→K^{+}\nu\bar{\nu}$ is performed with data sample corresponding to $63~fb^{−1}$ collected at the Υ(4S) resonance by the Belle II experiment. A novel measurement method is developed, which exploits topological properties of the decay that differ from both generic B-meson decays and light-quark pair-production. This inclusive tagging approach has the benefit of a higher signal efficiency compared to previous searches for this rare decay. As no significant signal is observed, an upper limit on the branching fraction of $B^{+}→K^{+}\nu\bar{\nu}$ = $4.1 \times 10^{−5}$ is set at the 90% confidence level. We will talk about this novel analysis technique and the result.

Speaker: Simon Kurz (BELLE (BELLE II Experiment))

21_EPS_BtoKnunu_and_other_SimonKurz.pdf

494 Planck Safety and Flavor Physics

We introduce the property of Planck safety as paradigm for model building. Extensions of the SM are constructed featuring vector-like fermions and a flavor matrix scalars. Yukawa interactions interlocking the SM and BSM sector act as flavor portals that allow to address experimental anomalies, while taming Landau poles and stabilizing the Higgs potential up to the Planck scale.

Speaker: Tom Steudtner (TU Dortmund)

bsm.pdf

495 Tests of the Standard Model by means of $\Upsilon(3S)$ meson decays with the $BABAR$ detector

The $BABAR$ detector collected a sample of 122 million $\Upsilon(3S)$ mesons, corresponding to an integrated luminosity of 28 fb$^{-1}$, operating the PEP-II $e^+e^-$ collider at a center-of-mass energy of about 10.355 GeV. This sample is the largest ever collected at that energy and provides unique opportunities to test several aspects of the Standard Model.
We report on a precision measurement of the ratio $R_{\tau\mu} = BF(\Upsilon(3S)\to\tau^+\tau^-)/BF(\Upsilon(3S)\to\mu^+\mu^-)$. The result is in agreement with the Standard Model prediction and its uncertainty is almost an order of magnitude smaller than the only previous measurement reported by the CLEO collaboration. We also present a search for the Lepton Flavour Violating decays $\Upsilon(3S)\to e^{\pm}\mu^{\mp}$, unobservable in the SM, but predicted to be enhanced in several new physics extensions.

Speaker: Nafisa Tasneem

ntasneem_EPS_2021.pdf

ntasneem_EPS_2021.pptx

496 Status of the Mu2e experiment at Fermilab

The Mu2e experiment at Fermilab aims to measure the charged-lepton flavour violating (CLFV) neutrino-less conversion of a negative muon into an electron in the field of a nucleus. The conversion process results in a monochromatic electron with an energy slightly below the muon rest mass (104.97 MeV). The Goal of the experiment is to improve by four orders of magnitude the previous measurement and reach a single event sensitivity of 3 x 10^{-17} on the conversion rate with respect to the muon capture rate.

Although the SM is very well tested in many regimes, it appears likely to be incomplete. In many of the Beyond the Standard Model (BSM) scenarios, rates for CLFV processes are within the reach of the next generation of experiments. In particular, if SUSY particles have masses and couplings within the discovery reach of the LHC, CLFV rates will be observable. On the contrary, many CLFV searches have a sensitivity to new physics that exceeds the LHC, bringing the reach of new mass scales up to 10^4 TeV. In this pursuit, indirect measurements of CLFV will be crucial evidence of new physics.

The experiment goal is achieved by sending a very intense pulsed negative muon beam to an Aluminium target to collect a total of 10^{18} stopped muons in a few years of running. Production and transport of the muons are accomplished by means of a large (25 m length) and sophisticated magnetic system composed of production, transport, and detector solenoids. The magnetic systems allows the very intense beam to be directed on target with a low request on power.

The improvements with respect to previous conversion experiments are based on four elements: the higher muon intensity, the pulsed beam structure, the extinction of out of time particles and the precise electron identification in the detector solenoid. The conversion electron will be reconstructed and separated from the Decay in Orbit (DIO) background by a very high resolution tracking system based on straw technology. The crystal calorimeter system will confirm that the candidates are indeed electrons by performing a powerful mu/e rejection while granting a tracking-independent HLT filter. A Cosmic Ray Veto system surrounds the detector solenoid to make the cosmic based background negligible.

The Mu2e experiment is under construction at the Muon Campus of Fermilab, having received CD-3 approval in July 2016. The construction of the magnetic system is still dominating the critical path of the experiment. In the current schedule, after a long installation and commissioning phase with cosmic rays in the position extracted from the solenoid, the experiment start is foreseen for the beginning of 2024 and will be organised in two phases, a first one at low and a second one at full beam intensity.

Speaker: Stefano Di Falco (INFN Pisa)

difalco_eps2021.pdf

497 Radiative b-decays at LHCb

Radiative b-hadron decays are sensitive probes of New Physics through the study of branching fractions, CP asymmetries and measurements of the polarisation of the photon emitted in the decay. In particular, these measurements help constraining the size of right-handed currents in extensions of the Standard Model. Large samples of radiative b-decays have been collected by the LHCb experiment during Run1 and Run2. We present here the most recent LHCb measurements in this kind of decays.

Speaker: Pere Gironella Gironell (Universitat de Barcelona)

RadBDecays_LHCb_pgironella.pdf

T09: Higgs Physics: Prospects - part 1

Conveners: Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris), Michael Trott (NBI), meng xiao (zhejiang university), Sarah Heim (DESY)

498 Prospects of non-resonant and resonant Higgs pair production at the HL-LHC

A direct measurement of the Higgs self coupling is very crucial to understand the nature of electroweak symmetry breaking. This requires an observation of production of Higgs boson pair, which suffers from very low event rate even at the current LHC run. In our work, we study the prospects of observing the non-resonant Higgs pair production at the high luminosity run of the 14 TeV LHC (HL-LHC). Here, we choose multiple final states based on the event rate and cleanliness, namely, $b\bar{b}\gamma \gamma$, $b\bar{b} \tau^+ \tau^-$, $b\bar{b} WW^*$, $WW^*\gamma \gamma$ and $4W$ channels and do a collider study by employing a cut-based as well as multivariate analyses using the Boosted Decision Tree (BDT) algorithm. We also consider various physics beyond the standard model (BSM) scenarios, for example resonant Higgs pair production, to quantify the effects of contamination when one tries to measure the SM di-Higgs signals. In a later study, we search specifically for the heavy resonant scalars ($H/A$) via their decay into two SM Higgs boson at the HL-LHC. After performing multivariate analysis using BDT algorithm in various final states, we set upper limits on the production cross-section of heavy scalar times its branching ratio into final state products for different values of heavy scalar masses. Finally, we translate these limits and put strong constraints on the $m_A-tan\beta$ parameter space (where $m_A$ and $tan\beta$ are respectively the mass of the pseudoscalar and the ratio of the vacuum expectation values of the two Higgs doublets) in the context of Minimal Supersymmetric Standard Model (MSSM).

Speaker: Mr Amit Adhikary (Indian Institute of Science)

EPS-HEP21_AmitAdhikary.pdf

499 ILC Higgs physics potential

Higgs factories based on e+e- colliders have the potential to measure the complete profile of the Higgs boson at a level of precision that goes qualitatively beyond the expect capabilities of the LHC. This talk will review the program of Higgs boson coupling measurements expected from the International Linear Collider, including the most recent updates. These measurements span the range of e+e- CM energies from 250 GeV to 1 TeV, and include precision measurements of the top quark Yukawa coupling and the Higgs self-coupling.

Speaker: Shin-ichi Kawada (FLC)

SK_EPS_2021Jul29.pdf

500 Higgs invisible and rare decays at ILC

The operation of an e+e- collider at a CM energy of 250 GeV will yield a large sample of Higgs bosons that are tagged by recoil against an observed Z boson at a fixed laboratory energy. By selecting these Z bosons and looking on the other side of the event, e+e- colliders will be sensitive to essentially all possible rare and exotic Higgs boson decay channels, in most cases down to branching ratios of order 10^{-4}. This includes channels important for theories beyond the Standard Model such as H-> b bbar + (missing energy) and H-> b sbar that are very difficult to observe at the LHC. This talk will review the expectations for the discovery of new decay modes of the Higgs boson at the International Linear Collider.

Speaker: Chris Potter (University of Oregon)

POTTER_EPSHEP2021.pdf

501 A combined fit to the Higgs Branching Ratios at ILD

We introduce here a new method to measure the Higgs decay branching ratios at future $e^+e^-$ Higgs factories, by directly exploiting class numeration. Given the clean environment at a lepton collider, we build an event sample highly enriched in Higgs bosons and essentially unbiased for any decay mode. The sample can be partitioned into categories using event properties linked to the expected Higgs decay modes. The counts per category are used to fit the Higgs branching ratios in a model independent way. The result of the fit is directly the set of branching ratios, independent from any measurement of a Higgs production mode. Special care is given to an appropriate treatment of the statistical uncertainties. In this contribution, the current status of our implementation of this analysis within the ILD concept detector is presented.

Speaker: Jonas Kunath (LLR – CNRS, École polytechnique, Institut Polytechnique de Paris, 91120 Palaiseau, France.)

ILD_combined_higgs_brs_EPS-HEP2021.pdf

502 Higgs and double Higgs production at CLIC e+e- energies up to 3 TeV

The Compact Linear Collider (CLIC) is a mature option for a future electron-positron collider operating at centre-of-mass energies of up to 3 TeV. CLIC would be built and operated in a staged approach with three centre-of-mass energy stages currently assumed to be 380 GeV, 1.5 TeV, and 3 TeV. This presentation provides a full overview of the CLIC Higgs physics potential in both the Higgsstrahlung (e+e- => ZH) and vector-boson fusion (e+e- => Hnunu) production modes at the three CLIC stages. The studies have been performed in full simulation. Latest results include Higgstrahlung at the highest energy, which is of particular interest as contributions from BSM effects to this process grow with energy. Ongoing studies of the Higgs branching ratio to photons at 3 TeV, as wells as ZZ* decay at various energies will also be included. The presentation includes latest results on the extraction of the Higgs self-coupling from double Higgs production at 1.5 TeV and 3 TeV. The Higgs self-coupling is of particular interest for determining the shape of the Higgs potential and for its sensitivity to a variety of BSM physics scenarios. At the higher-energy stages CLIC will produce Higgs boson pairs both via double Higgsstrahlung and via vector-boson fusion. Measurements of these processes lead to a determination of the Higgs self-coupling with a precision around 10%.

Speaker: Lars Rickard Stroem (ATLAS (ATLAS SM and Beyond))

clic_higgs_eps_hep_stroem.pdf

503 mb(mH): extracting the bottom quark mass from Higgs precision measurements

A new method is presented to extract the bottom quark mass from collider data on Higgs production and decay rates. We find a value for the bottom quark MSbar mass at the scale of the Higgs boson mass of mb(mh) = 2.6 +/- 0.3 GeV from recent measurements of Higgs coulings by the ATLAS and CMS experiments at the CERN LHC. This result is compatible with the prediction of mb(mh) from the evolution of the world average for mb(mb) and thus provides further evidence for the scale evolution, or "running" of the bottom quark mass. Future precision measurements of Higgs decay rates are expected to improve this result considerably. We assess, in particular, the potential of the complete HL-LHC program and of a future "Higgs factory" electron-positron collider.

Speaker: Marcel Vos (IFIC (UVEG/CSIC) Valencia)

bottom_quark_and_higgs_boson.pdf

504 Higgs measurements at the Future Circular Colliders

Precision measurements and searches for new phenomena in the Higgs sector are among the most important goals in particle physics. Experiments at the Future Circular Colliders (FCC) are ideal to study these questions. Electron-positron collisions (FCC-ee) up to an energy of 365 GeV provide the ultimate precision with studies of Higgs boson couplings, mass, total width, and CP parameters, as well as searches for exotic and invisible decays. Very high energy proton-proton collision (up to 100 TeV) provided by the FCC-hh will allow studying the Higgs self-coupling. There is a remarkable complementarity of the FCC-ee and FCC-hh colliders, which in combination offer the best possible overall study of the Higgs boson properties.

Speaker: Sylvie Braibant (Bologna University and INFN sezione di Bologna)

HiggsAtFCC.pdf

T10: Searches for New Physics: Part 8

All talks in this session will be 12 mins + 3 mins for the discussion.

Conveners: Akitaka Ariga (Chiba University), Pedro Schwaller (Johannes Gutenberg University Mainz)

505 Results and future plans of the MoEDAL experiment

The unprecedented collision energy of the LHC has opened up a new discovery frontier. Unfortunately, signs of new physics have yet to be seen. The LHC's first dedicated search experiment, MoEDAL, started data taking for LHC's Run-2. MoEDAL is designed to search highly ionising particle avatars of new physics using p-p and heavy-ion collisions at the LHC. The planned upgrade for MoEDAL at Run-3 - the MAPP detector ( MoEDAL Apparatus for Penetrating Particles) - will extend MoEDAL's physics reach to include feebly interacting and long lived messengers of physics beyond the Standard Model. This will allow us to explore a number of models of new physics, including dark sector models, in a complementary way to that of conventional LHC collider detectors. Further to this, a possible astroparticle extension to MoEDAL, called Cosmic-MoEDAL, will allow the search for magnetic monopoles to be continued from the TeV scale to the GUT scale. The presentation focuses on recent results and plans for the LHC Run 3.

Speaker: Dr Vasiliki Mitsou (IFIC - CSIC / Valencia Univ.)

Mitsou-MoEDAL-EPS2021.pdf

506 FASER: Forward Search Experiment at the LHC

The FASER experiment is a new small and inexpensive experiment that is being placed 480 meters downstream of the ATLAS experiment at the CERN LHC. The experiment will shed light on currently unexplored phenomena, having the potential to make a revolutionary discovery. FASER is designed to capture decays of exotic particles, produced in the very forward region, out of the ATLAS detector acceptance. This talk will present the physics prospects, the detector design, and the construction progress of FASER. The experiment has been successfully installed and will take data during the LHC Run-3.

Speaker: Di Wang (Tsinghua University)

FASER_EPS.pdf

507 Searching for millicharged particles in future proton-proton collisions at the LHC

We report on the expected sensitivity of dedicated scintillator-based detectors at the LHC for elementary particles with charges much smaller than the electron charge. Having secured the necessary funding, we plan to construct two detectors, including a novel slab detector configuration, for the LHC Run 3. The dataset provided by a prototype scintillator-based detector has been used to characterise the performance of these detectors and provide an accurate background projection. With the Run 3 dataset, we expect sensitivity to new particles with masses between 10 MeV and 45 GeV for charges between 0.003e and 0.3e, depending on their mass. We also consider upgraded detectors for the HL-LHC dataset, for which we expect sensitivity to masses between 10 MeV and 80 GeV for charges between 0.0018e and 0.3e, depending on their mass.

Speaker: Francesco Setti (UCSB)

FrancescoSetti_milliQan_EPS.pdf

508 Physics Beyond SM at the HL-LHC with CMS

The High-Luminosity Large Hadron Collider (HL-LHC) is expected to deliver an integrated luminosity of up to 3000 fb-1. The very high instantaneous luminosity will lead to about 200 proton-proton collisions per bunch crossing (“pileup”) superimposed to each event of interest, therefore providing extremely challenging experimental conditions. Prospects for future BSM Physics studies at the HL-LHC at CMS are presented.

Speaker: Bhawna Gomber (Saha)

EPS2021_BhawnaGomber_final.pdf

509 Flavorful leptoquarks at the LHC and beyond: Spin 1

Evidence for electron-muon universality violation that has been revealed in $b\to s \ell\ell$ transitions in the observables $R_{K,K^*}$ by the LHCb Collaboration can be explained with spin-1 leptoquarks in $SU(2)_L$ singlet $V_1$ or triplet $V_3$ representations in the ${\cal{O}}(1-10)$ TeV range. We explore the sensitivity of the high luminosity LHC (HL-LHC) and future proton-proton colliders to $V_1$ and $V_3$ in the parameter space connected to $R_{K,K^*}$-data. Future sensitivity projections based on extrapolations of existing ATLAS and CMS searches are worked out. We find that for $\kappa=1$ the mass reach for pair (single) production of $V_1$ can be up to 3 TeV (2.1 TeV) at the HL-LHC and up to 15 TeV (19.9 TeV) at the FCC-hh with $\sqrt{s}=100$ TeV and $20 \,\mbox{ab}^{-1}$. The mass limits and reach for the triplet $V_3$ are similar or higher, depending on flavor. While there is the exciting possibility that leptoquarks addressing the $R_{K,K^*}$-anomalies are observed at the LHC, to fully cover the parameter space $pp$-collisions beyond the LHC-energies are needed.

Speaker: Ivan Nišandžić (Ruđer Bošković Institute)

EPS_2021_Nisandzic.pdf

510 Triggering long-lived particles in HL-LHC and the challenges in the first stage of the trigger system

Triggering long-lived particles (LLPs) at the first stage of the trigger system is very crucial in LLP searches to ensure that we do not miss them at the very beginning. The future High Luminosity runs of the Large Hadron Collider will have an increased number of pile-up events per bunch crossing. There will be major upgrades in hardware, firmware and software sides, like tracking at level-1 (L1). The L1 trigger menu will also be modified to cope with pile-up and maintain the sensitivity to physics processes. In our study we found that the usual level-1 triggers, mostly meant for triggering prompt particles, will not be very efficient for LLP searches in the 140 pile-up environment of HL-LHC, thus pointing to the need to include dedicated L1 triggers in the menu for LLPs. We consider the decay of the LLP into jets and develop dedicated jet triggers using the track information at L1 to select LLP events. We show in our work that these triggers give promising results in identifying LLP events with moderate trigger rates.

Speaker: PRABHAT SOLANKI (Indian Institute of Science, Bangalore)

EPS-HEP_Solanki.pdf

511 BSM Physics at the LHeC and the FCC-he

The LHeC and the FCC-he offer fascinating, unique possibilities for discovering BSM physics in DIS, both due to their large centre-of-mass energies and high luminosities. In this talk we will review most recent studies as presented in the 2020 LHeC Conceptual Design Report update [1]. We will show the prospects for observing extensions of the Higgs sectors both with charged and neutral scalars, anomalous Higgs couplings and exotic decays. Then we will discuss searches for R-parity conserving and violating supersymmetry both with prompt and long-lived particles, and of feeble interacting particles like sterile neutrinos, fermion triplets, dark photons and axion-like particles. Finally we will address anomalous couplings and searches for heavy resonances like leptoquarks and vector-like quarks, excited fermions and colour-octet leptons.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e-Print: 2007.14491 [hep-ex], to appear in J. Phys. G.

Speaker: Oliver Fischer

EPS21_Fischer_BSMatEP.pdf

512 The HighNESS Project and Future Free Neutron Oscillations Searches at the ESS

The European Spallation Source ESS, presently under construction, in Lund, Sweden, is a multi-disciplinary international laboratory. It will operate the world's most powerful pulsed neutron source. Taking advantage of the unique potential of the ESS, the NNBAR collaboration proposed a two-stage program of experiments to perform high precision searches for neutron conversion in a range of baryon number violation (BNV) channels culminating in an ultimate sensitivity increase for $n \to \bar{n}$ oscillations of three orders of magnitude over the previously attained limit obtained at the Institut Laue-Langevin ILL.
The first stage of this program HIBEAM (High Intensity Baryon Extraction and Measurement) will employ the fundamental physics beamline during the first phase of the ESS operation. This stage focuses principally on searches for neutron conversion to sterile neutrons $n'$ that would belong to a ``dark" sector.
The second stage, NNBAR, will exploit a large beam port, specifically designed in the ESS target station monolith for this experiment, to deliver the maximum possible neutron flux and search directly for $n \to \bar{n}$ oscillations.
Supported by a 3 MEuro Research and Innovation Action within the EU Horizon 2020 program, a design study (HighNESS) is now underway for the design of the ESS second neutron source which will be optimized in order to boost the performance of the NNBAR experiment.
This talk will focus on the HighNESS program and the ongoing developments in the NNBAR collaboration.

Speaker: Valentina Santoro (European Spallation Source)

EPS_santoro_v1.pptx.pdf

T11: Quantum Field and String Theory: Part 3

513 Four-loop scattering amplitudes journey into the forest

A crucial challenge in perturbative Quantum Field Theory is the description of quantum fluctuations at high-energy scattering processes by the calculation of multi-loop scattering amplitudes. Aiming for improving the efficiency of these computations, we delve into a new technique based on the Loop-Tree Duality (LTD). We analyse the multiloop topologies that appear for the first time at four loops and manage to assemble them in general expression, the N^4MLT universal topology. Based on the fact that the LTD enables to open any scattering amplitude in terms of convolutions of known subtopologies, we obtained the dual representation of the universal N^4MLT topology and determined the internal causal structure of the entire amplitude. Remarkably, we verified the causal conjecture for the N^4MLT family and present explicit causal representations of selected configurations, allowing a more efficient numerical implementation due to the absence of non-causal singularities.

Speaker: Norma Selomit Ramírez Uribe (IFIC CSIC-UV)

Selomit_Ramirez_EPS_2021.pdf

514 Massive Integrability: From Fishnet Theories to Feynman Graphs and Back

Since the rise of the AdS/CFT duality, integrability has proven to be an important tool to advance our understanding of massless QFT. In this talk we demonstrate that integrability is also present in massive QFT in D>2 spacetime dimensions. We show that large classes of massive Feynman integrals are highly constrained by an infinite dimensional Yangian symmetry. When translated to momentum space, this leads to a novel massive generalization of conformal symmetry. Finally, we argue that these features of Feynman integrals can be understood as the integrability of planar scattering amplitudes in a massive version of the so-called fishnet theory, which is obtained as a double-scaling limit of N=4 super Yang-Mills theory on the Coulomb branch.

Speaker: Florian Loebbert (Humboldt University Berlin)

TalkEPS-HEPJul2021-FlorianLoebbert.pdf

515 Generalizing the Ryu-Takayanagi formula to probe entanglement shadows of BTZ black holes

We define a generalized entanglement measure in the context of AdS$_3$/CFT$_2$. Compared to the ordinary entanglement entropy between spatial degrees of freedom dual to the area of the Ryu-Takayanagi surface, we take into account both entanglement between spatial degrees of freedom as well as between different fields of the boundary CFT. We then calculate this generalized entanglement measure in a thermal state dual to the BTZ black hole in the setting of the D1/D5 system at and close to the orbifold point. We find that the entanglement entropy defined in this way is dual to the length of a geodesic with non-zero winding number. Such geodesics probe the entire bulk geometry, including regions known as entanglement shadows which are not reached by any Ryu-Takayanagi surface. This allows us to describe regions close to the black hole horizon in the one-sided black hole and the wormhole growth in the case of a two-sided black hole from entanglement data in the boundary field theory. Therefore, we propose that entanglement is in fact enough to reconstruct the full BTZ geometry from boundary data.

Speaker: Marius Gerbershagen (Universität Würzburg)

Slides_EPS-HEP2021_MariusGerbershagen.pdf

516 Non-Hermiticity: a new paradigm for model building in particle physics

Non-Hermitian quantum theories have been applied in many other areas of physics. In this talk, I will review recent developments in the formulation of non-Hermitian quantum field theories, highlighting features that are unique compared to Hermitian theories. I will describe their crucial discrete symmetries and how continuous symmetry properties are borne out, including Noether's theorem [1], the Goldstone theorem [2] and the Englert-Brout-Higgs mechanism [3,4]. As examples, I will describe non-Hermitian deformations of QED, the Higgs-Yukawa theory [5] and flavour oscillations [6], illustrating the potential implications of non-Hermitian model building for the neutrino sector [5]. Together, these results pave the way for a systematic programme for building non-Hermitian extensions of the Standard Model of particle physics.

[1] J. Alexandre, P. Millington, D. Seynaeve, Phys. Rev. D 96, 065027 (2017).
[2] J. Alexandre, J. Ellis, P. Millington, D. Seynaeve, Phys. Rev. D 98, 045001 (2018).
[3] J. Alexandre, J. Ellis, P. Millington, D. Seynaeve, Phys. Rev. D 99, 075024 (2019).
[4] J. Alexandre, J. Ellis, P. Millington, D. Seynaeve, Phys. Rev. D 101, 035008 (2020).
[5] J. Alexandre, C. M. Bender, P. Millington, J. High Energy Phys. JHEP11(2015)111.
[6] J. Alexandre, J. Ellis, P. Millington, Phys. Rev. D 102, 125030 (2020).

Speaker: Peter Millington (University of Nottingham)

EPSHEP2021 [Millington].pdf

517 Probing Unified Theories with Reduced Couplings at Future Colliders

The search for renormalization group invariant relations among parameters to all orders in perturbation theory constitutes the basis of the reduction of couplings concept. Reduction of couplings can be achieved in certain N=1 supersymmetric grand unified theories and few of them can even become finite at all loops. The resulting theories in which successful reduction of couplings has been achieved so far include: (i) a reduced version of the minimal N=1 SU(5) model, (ii) an all-loop finite N=1 SU(5) model, (iii) a two-loop finite N=1 SU(3)^3 model and finally (vi) a reduced version of the Minimal Supersymmetric Standard Model. We present a number of benchmark scenarios for each model and investigate their observability at existing and future hadron colliders. The heavy supersymmetric spectra featured by each of the above models are found to be beyond the reach of the 14 TeV HL-LHC. It is also found that the reduced version of the MSSM is already ruled out by the LHC searches for heavy neutral MSSM Higgs bosons. In turn, the discovery potential of the 100 TeV FCC-hh is investigated and found that large parts of the predicted spectrum of these models can be tested. In this talk we will present results and updates from our recent work (Eur.Phys.J.C 81 (2021) 2,185: arXiv:2011.07900 [hep-ph]).

Speaker: Gregory Patellis (National Technical University of Athens)

patellis_EPS-HEP2021.pdf

518 The strong CP problem, the infinite volume limit, and cluster decomposition

While CP violation has never been observed in the strong interactions, the QCD Lagrangian admits a CP-odd topological interaction proportional to the so called theta angle, which weighs the contributions to the partition function from different topological sectors. The observational bounds are usually interpreted as demanding a severe tuning of theta against the phases of the quark masses, which constitutes the so-called strong CP problem. In this talk we challenge this view and argue that in an infinite spacetime the theta angle drops out of correlation functions, so that it becomes unobservable and the CP symmetry is preserved. We arrive at this result either by using instanton computations or by constraining the dependence of the partition function on the spacetime volume and the fermion masses by imposing cluster decomposition and compatibility with the index theorem. We further show that in large but finite spacetime volumes, cluster decomposition can be satisfied up to volume-suppressed corrections without the need to sum over topological sectors, and the resulting partition functions lead again to no CP violation.

Speaker: Carlos Tamarit (Technische Universität München)

Strong_CP_short.pdf

T12: Detector R&D and Data Handling: LHC Run 4, Run 5

Conveners: Magnus Mager (CERN), Alessandro Cardini (INFN Sezione di Cagliari, Italy)

519 Scintillating sampling ECAL technology for the Upgrade II of LHCb

The aim of the LHCb Upgrade II is to operate at a luminosity in the range of 1 to 2 $\times$ 10$^{34}$ cm$^{-2}$ s$^{-1}$ to collect a data set of 300 fb$^{-1}$. This will require a substantial modification of the current LHCb ECAL due to high radiation doses in the central region and increased particle densities. The ECAL has to provide good energy and position resolutions in these conditions. Timing capabilities with tens of picoseconds precision for neutral electromagnetic particles and increased granularity with dense absorber in the central region are needed for pile-up mitigation.
An attractive option for the central region is SPACAL technology with radiation-hard scintillating crystal fibers and tungsten absorber, and organic scintillating fibers with lead absorber in the intermediate region. Results from an ongoing R&D campaign to optimise the Upgrade II ECAL are shown. This includes studies of radiation-hard scintillation materials, performance optimisation using detailed simulations and test beam measurements. The presentation also includes an overview of the overall plans for the Upgrade II of the LHCb ECAL.

Speaker: Philipp Roloff (CERN)

eps_2021_roloff_version3.pdf

520 The upgrade of the CMS Electromagnetic Calorimeter for HL-LHC

The Electromagnetic Calorimeter (ECAL) of the CMS detector has played an important role in the physics program of the experiment, delivering outstanding performance throughout data taking. The High-Luminosity LHC will pose new challenges. The four to five-fold increase of the number of interactions per bunch crossing will require superior time resolution and noise rejection capabilities. For these reasons the electronics readout has been completely redesigned. A dual gain trans-impedance amplifier and an ASIC providing two 160 MHz ADC channels, gain selection, and data compression will be used in the new readout electronics. The trigger decision will be moved off-detector and will be performed by powerful and flexible FPGA processors, allowing for more sophisticated trigger algorithms to be applied. The upgraded ECAL will be capable of high-precision energy measurements throughout HL-LHC and will greatly improve the time resolution for photons and electrons above 10 GeV. The results in terms of performance achieved with a prototype system in a vertical integration test will be presented.

Speaker: Dario Soldi (INFN-Torino)

EPS2021_refined.pdf

521 Future upgrades of ALICE for Run 4

As ALICE is commissioning the detectors after major upgrades for the upcoming LHC Run 3, further projects are already on their way. R&D for a future upgrade of the Inner Tracking System has demonstrated the feasibility to operate thinned monolithic active pixel sensors bent to radii as small as 18 mm. In addition, it has been confirmed that large-scale wafers can be bent to such radii to form truly cylindrical sensors requiring only the silicon itself in the active area. This technique shall be used to replace the inner tracking layers and achieve unprecedented low material budget, reduced interaction probabilities, and unparalleled vertexing performance. We will discuss the results from the R&D programme and the prospects for the ITS3.

In addition, a novel concept for a Forward Calorimeter (FoCal) consisting of a high-granularity Si-W electromagnetic calorimeter with pad and pixel readout to provide unprecedented spatial resolution, and a hadronic calorimeter with conventional metal-scintillator technology with optical readout. The FoCal covers the pseudorapidity range from 3.4 to 5.8 to measure forward photon production to constrain the gluon PDFs down to very small x. We will show results from the R&D programme and the prospects for physics with the FoCal.

Speaker: Filip Krizek

Krizek_EPS21_v4.pdf

522 Upgrade of the CSC Muon System for the CMS Detector at the HL-LHC

The Large Hadron Collider (LHC) will be upgraded in several phases to significantly expand its physics program. After the current long shutdown from 2018-2021 (LS2) the accelerator luminosity will be increased to 2 − 3 * 10^34cm−2s−1 exceeding the design value of 1 * 10^34cm−2s−1 allowing the CMS experiment to collect approximately 100 fb−1/year. A subsequent upgrade in 2022-23 will increase the luminosity up to 5 * 10^34cm−2s−1. The CMS muon system must be able to sustain a physics program after the LS2 shutdown that maintains sensitivity to electroweak scale physics and for TeV scale searches similar to what was achieved up to now For the Cathode Strip Chamber (CSC) muon detectors. The on chamber front-end readout electronics portion of the CSC electronics upgrade has now been completed. The design of the upgraded CSC electronics will be discussed as well as the status of the commissioning of the upgraded CSC system. In view of the operating conditions at HL-LHC, it is vital to asses the detector performance for high luminosity. Accelerated aging tests are being performed to study the behavior of the CSC detectors under conditions which are nearly an order of magnitude beyond the original design values. The status of this irradiation campaign and results will be presented.

Speaker: Yacine Haddad (Northeastern University)

CSC-MUON-UPGRADE-EPS.pdf

523 The HL-LHC Upgrade of the ATLAS Tile Hadronic Calorimeter

The High-Luminosity phase of LHC, delivering five times the LHC nominal instantaneous luminosity, is scheduled to begin in late 2027. The ATLAS Tile Hadronic Calorimeter (TileCal) will need new electronics to meet the requirements of a 1 MHz trigger, higher radiation dose, and to ensure sound performance under high pile-up conditions. Both the on- and off-detector TileCal electronics will be replaced during the shutdown of 2025-2027. PMT signals from every TileCal cell will be digitized and sent directly to the back-end electronics, where the signals are reconstructed, stored, and sent to the first level of trigger at a rate of 40 MHz. This will provide better precision of the calorimeter signals used by the trigger system and will allow the development of more complex trigger algorithms. The TileCal upgrade program has undergone extensive R&D and beam tests. A miniature "demonstrator" module has been tested in actual detector conditions. We will present the results of these studies.

Speaker: Danijela Bogavac (Barcelona)

DBogavac_TileCal_EPS.pdf

524 Full-system commissioning of TGC frontend electronics for Phase-2 LHC-ATLAS

The Thin Gap Chambers (TGCs) of the LHC-ATLAS are responsible for triggering muons in the endcap region at the hardware trigger stage. The frontend system of TGC will be upgraded for HL-LHC to send binary hit-map at every bunch crossing (BC) to the backend system. Such an operation requires lots of unique challenges: high-performance hit BC Identification, fine-tuned clock distribution, and the capability of timing calibration. Accommodating these requirements, the primary processor board (PS-Board) is in charge of data processing and reception of control signals distributed by the backend. An independent control module (JATHub) will take responsibility for FPGA configuration and clock phase monitoring of the PS-Boards with an SoC-based design. The timing calibration methodology for fine-tuning the clock phase and signal timing is migrated with highly-extended flexibility in the Phase-2 system, exploiting the experience accumulated through the construction, commissioning, and operation of the existing TGC system. System-level commissioning has been launched at KEK with prototypes of PS-Boards and JATHub and analogue frontend electronics of Amplifier-Shaper-Discriminator (ASD) cards. The full-chain testbed system allows us to demonstrate fundamental functionalities of Trigger, Readout, Control and Calibration: clock phase fine-tuning, signal timing calibration, and hit readout with test pulse injection to ASD channels with adjusted timing parameters.

Speaker: Takumi Aoki (Tokyo University)

aoki_20210729_epshep_v11.pdf

525 The ATLAS detector evolution towards the High Luminosity era

After 9 years of successful operation in proton-proton collisions reaching up to $\sqrt{s}$=13 TeV, the ATLAS detector started in 2018 the preparations for an ambitious physics program, aiming the exploration of very rare processes and extreme phase spaces, an endeavor that will require a substantial increase in the integrated luminosity. To accomplish this purpose, a comprehensive upgrade of the detector and associated systems was devised and planned to be carried out in two phases. ThePhase-I upgrade foresees new features for the muon detector, for the EM calorimeter trigger system and for all trigger and data acquisition chain. For the
Phase-II upgrade, ATLAS will fully replace its inner tracker, install a new timing detector and the calorimeters and muon systems will operate on a free-running readout scheme. This presentation will summarize the expected performance of the aforementioned projects, as well as the new insights gained during the construction phase. This abstract is being submitted by the ATLAS Upgrade Speaker Committee representative. If approved, the speaker will be selected from ATLAS Collaboration and the conference will be informed.

Speaker: Jochen Jens Heinrich (Oregon)

210729_EPSHEP2021.pdf

526 ALICE 3

In parallel to the commissioning of the upgraded detector system for Run 3 and the R&D for upgrades planned for Run 4, ALICE is preparing a next-generation heavy-ion experiment for LHC Run 5. It will give us access to novel measurements of electromagnetic and hadronic probes of the QGP at very low momenta that will remain inaccessible in LHC Run 3+4, both because of detector performance and luminosity. We expect new insights from new measurements of multi-charm baryons and exotica as well as from high-precision analyses of dielectron production at very low momenta. The required detector performance shall be achieved through extensive usage of thin silicon sensors for tracking, combining the advantages of extremely low material budget, fast read-out, and high resolution. A modern particle identification system shall complement the tracking system. In combination with a silicon-based time of flight detector, a RICH and preshower detector are studied to provide high-purity measurements of dielectron pairs which probe the conditions in the QGP phase of the collision and help with the background rejection in the heavy-flavour measurements. We will present the physics prospects for heavy-ion physics in LHC Run 5 and beyond and the plans for the apparatus.

Speaker: Gian Michele Innocenti

20210712_ICHEP2021_ALICE3_v6_final.pdf

11:30 Lunch Break

Plenary Session 3

Convener: Mauro Mezzetto

527 Multi-messenger Astroparticle Physics

Speaker: Anna Franckowiak (DESY)

Franckowiak_EPS-HEP_2021_upload.pdf

recording

528 Dark Matter and Axion Searches

Speaker: Babette Döbrich

EPS_DM_BD_28jul.pdf

recording

529 Gravitational Waves

Speaker: Samaya Nissanke

EPSplenary2021_upload_nissanke.pdf

recording

530 Observational Cosmology

Speaker: Ariel Goobar

Goobar_EPS-HEP2021.pdf

recording

14:30 Break

Review Stream 1: Session 3

Convener: Beate Heinemann (DESY and Freiburg University)

531 Calculational Techniques in Particle Theory

Speaker: Lorenzo Tancredi (CERN TH)

EPS_2021_Tancredi.pdf

recording

532 Rare Decays and CP violation

Speaker: Paula Alvarez Cartelle

RD_and_CPV_PAlvarez_v2.pdf

recording

Review Stream 2: Session 3

Convener: Bostjan Golob

533 Neutrino Physics with Particle Beams

Speaker: Sara Bolognesi

bolognesi.pdf

recording

534 Neutrino Theory

Speaker: Thomas Schwetz-Mangold (KIT)

EPS-HEP_Schwetz.pdf

recording

535 Future Astroparticle Facilities

Speaker: Teresa Montaruli

EPS-HEP2021-Montaruli.pdf

recording

16:15 Break

Additional Poster Session

All rooms are open and the posters can be watched, but the presenters might not be next to their posters. There will be limited technical support.

Click here to access the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions).

Please also check the information how to enter and navigate the rooms on our main conference web page.

Access to the poster session rooms (user name: "eps2021", password: the same as for the zoom sessions)

T02: Cosmology: Part 3

Convener: Thomas Konstandin (T (Cosmology))

536 Cosmological bubble friction in local equilibrium

In first-order cosmological phase transitions, the asymptotic velocity of expanding bubbles is of crucial relevance for predicting observables like the spectrum of stochastic gravitational waves, or for establishing the viability of mechanisms explaining fundamental properties of the universe such as the observed baryon asymmetry. In these dynamic phase transitions, it is generally accepted that subluminal bubble expansion requires out-of-equilibrium interactions with the plasma which are captured by friction terms in the equations of motion for the scalar field. This has been disputed in works pointing out subluminal velocities in local equilibrium arising either from hydrodynamic effects in deflagrations or from the entropy change across the bubble wall in general situations. We argue that both effects are related and can be understood from the conservation of the entropy of the degrees of freedom in local equilibrium, leading to subluminal speeds for both deflagrations and detonations. The friction effect arises from the background field dependence of the entropy density in the plasma, and can be accounted for by simply imposing local conservation of stress-energy and including field dependent thermal contributions to the effective potential. We illustrate this with explicit calculations of dynamic and static bubbles for a first-order electroweak transition in a Standard Model extension with additional scalar fields.

Speaker: Carlos Tamarit (Technische Universität München)

Bubble_friction.pdf

537 Cosmological implications of EW vacuum instability: constraints on the Higgs-curvature coupling from inflation

The current experimentally measured parameters of the Standard Model (SM) suggest that our Universe lies in a metastable electroweak vacuum, where the Higgs field is prone to vacuum decay to a lower state with catastrophic consequences. Our measurements dictate that such an event has not taken place yet, despite the many different mechanisms that could have triggered it in our past light-cone. The focus of our work has been to calculate the probability of the false vacuum to decay during the period of inflation and use it to constrain the last unknown renormalisable SM parameter $\xi$, which couples the Higgs field with space-time curvature. More specifically, we derived lower $\xi$-bounds from vacuum stability in three inflationary models: quadratic and quartic chaotic inflation, and Starobinsky-like power-law inflation. We also took the time-dependence of the Hubble rate into account both in the geometry of our past light-cone and in the Higgs effective potential, which is approximated with three-loop renormalisation group improvement supplemented with one-loop curvature corrections.

Speaker: Mr Andreas Mantziris (Imperial College London)

Mantziris_EPS_HEP_2021.pdf

538 Inflation with strongly non-geodesic motion: theoretical motivations and observational imprints

A new class of inflationary attractors characterized by a strongly non-geodesic motion has been discovered in the past few years. I will describe how they naturally arise in negatively curved field space, allowing to inflate on potentials that are steep in Planck units. In these scenarios, primordial fluctuations often experience a transient tachyonic instability, akin to the one occurring in axion gauge-field inflation, and which can be described by a single-field effective field theory with imaginary sound speed. Independently of its precise origin, I will show how this leaves a peculiar imprint in the form of primordial non-Gaussianities of flattened type for all higher-order correlation functions, and I will mention links with primordial black holes and specific signatures in the stochastic gravitational wave background.

Speaker: Sébastien Renaux-Petel (Institut d'Astrophysique de Paris)

EPS-Renaux-Petel.pdf

T04: Neutrino Physics: Astrophysical neutrinos and cosmology

Conveners: Bjoern Soenke Wonsak (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik)), Stefania Bordoni (Université de Genève)

539 RES-NOVA: archaeological Pb-based observatory for Supernova neutrino detection

RES-NOVA is a new proposed experiment for the hunt of neutrinos from core-collapse supernovae (SN) via coherent elastic neutrino-nucleus scattering (CE$\nu$NS) using an array of archaeological lead (Pb) based cryogenic detectors. The high CE$\nu$NS cross-section on Pb and the ultra-high radiopurity of archaeological Pb enable the operation of a high statistics experiment equally sensitive to all neutrino flavors. Thanks to these unique features, RES-NOVA will be as sensitive as the currently running neutrino observatories, while running a detector with a total active volume of only (60 cm)$^3$. RES-NOVA will be able to reconstruct the SN neutrino parameters with great accuracy (at the 10% level) and it will be sensitive to SN bursts from the entire Milky Way Galaxy with >5 $\sigma$ statistical significance. The expected detector performance and sensitivity will be presented.

Speaker: Nahuel Ferreiro Lachellini (Max Planck Institute)

eps_resnova.pptx

540 Long Range Interactions in Cosmology: Implications for Neutrinos

Cosmology is well suited to study the effects of long range interactions due to the large densities in the early Universe. In this talk, I will explore how the energy density and equation of state of a fermion system diverge from the commonly assumed ideal gas form under the presence of scalar long range interactions with a range much smaller than cosmological scales. In this scenario, "small"-scale physics can impact our largest-scale observations. As a benchmark, I will apply the formalism to self-interacting neutrinos, performing an analysis to present and future cosmological data. I will explore how this fully removes the cosmological neutrino mass bound, opening the possibility for a laboratory neutrino mass detection in the near future. I will also discuss an interesting complementarity between neutrino laboratory experiments and the future EUCLID survey.

Speaker: Ivan Esteban (CCAPP, Ohio State University)

Talk_Esteban.pdf

541 Meeting the challenges of relic neutrinos

After some introductory, motivational remarks, our [in collaboration with Bhupal Dev] attempts at confronting these challenges will be discussed in the context of Standard Model and beyond and experimental prospects at existing facilities as well as those being planned in the near future.

[Please note that i am also submitting an abstract for a parallel session talk in the Flavor and CP violation track. If the organizers want to limit me to only one talk my above one in the neutrino session is my top priority for this meeting]

Speaker: Amarjit Soni (BNL-HET)

final 4 EPS2021.pdf

T05: Heavy Ion Physics: Part 6

Note: All contributions are given 12 minutes + 3 min for questions

542 Measurement of light-by-light scattering in ultra-peripheral Pb+Pb collisions with the ATLAS detector

In ultra-relativistic heavy-ion collisions, one expects copious rates of $\gamma+\gamma$ processes through the interaction of the large electromagnetic fields of the nuclei which can lead to light-by-light scattering via loop diagrams. This process was directly observed for the first time in UPCs at the LHC by ATLAS. Final measurements of light-by-light scattering with full run 2 dataset with substantially reduced uncertainties will be presented. This process provides a precise and unique opportunity to investigate extensions of the Standard Model such as axion-like particles.

Speaker: Mateusz Dyndal (AGH UST Krakow)

mdyndal_eps2021_lbyl.pdf

543 From Wigner distributions of photons to dilepton production in semicentral heavy ion collisions

Ultrarelativistic Heavy Ions of large charge Z are accompanied by a large flux of Weizsacker–Williams photons. This opens up the opportunity to study a variety of single photon induced nuclear processes, as well as photon-photon processes.

We would like to present a formalism which allows to calculate differential distributions of dileptons produced via photon-photon fusion in semi-central (impact parameter $<$ 2 $\times$ nuclear radius) nucleus-nucleus collisions for a given centrality. In this approach the differential cross section is calculated using the complete polarization density matrix of photons resulting from the Wigner distribution formalism. We will present several differential distributions such as invariant mass of dileptons, dilepton transverse momentum and acoplanarity for different regions of centrality. The results of the calculations will be compared to experimental data of the STAR, ALICE and ATLAS collaborations. Very good agreement with the data is achieved without free parameters in all cases. Additional final state rescattering of leptons in the quark-gluon plasma is not needed. Our new approach based on Wigner distributions of photons gives a much better agreement with experimental data than the previous approaches used in the literature.

M. Kłusek-Gawenda, W. Schaefer and A. Szczurek,
``Centrality dependence of dilepton production via $\gamma \gamma$ processes from Wigner distributions of photons in nuclei,''
Phys. Lett. B814, 136114 (2021), [arXiv:2012.11973 [hep-ph]].

Speaker: Mariola Kłusek-Gawenda (IInstitute of Nuclear Physics Polish Academy of Sciences)

MKG_EPSHEP2021_organized.pdf

544 Di-muons production from two-photon scattering in Pb+Pb collisions with the ATLAS detector

Relativistic heavy ion beams are accompanied by a large flux of equivalent photons, giving rise to a set of photon-induced processes. These can lead to photon-photon interactions in both ultraperipheral collisions, where the nuclei do not overlap, as well as in hadronic processes accompanied by the production of hot, dense matter. The latter provides a potentially sensitive electromagnetic probe of the quark-gluon plasma. This talk presents a series of measurements of such processes performed by the ATLAS Collaboration. New measurements of exclusive di-muon production, which provide detailed constraints on the nuclear photon flux and its dependence on impact parameter and photon energy. In particular, the study of the di-muon cross sections in the presence of forward neutron production, provides an additional experimental handle on the impact parameter range sampled in the observed events. The same process of dileptons produced via two-photon scattering in non-ultra-peripheral (non-UPC) nucleus-nucleus collisions first measured by ATLAS and STAR showed an unexpected centrality-dependent broadening of the angular correlation between the two leptons and/or of the two-lepton $p_{\mathrm{T}}$ distribution. Full statistic of run 2 dataset allow new features to be observed in the data, both in the yields of the pairs as well as in their angular distributions. Differential measurements of the dependence of the pair-distribution on the transverse-momentum and rapidity of the two muons, as well as the dependence on the event centrality will be presented, and the possible physics implications will be discussed.

Speaker: Brian Cole (Columbia University)

GammaGammaDimuon-EPS2021_v2.pdf

545 Two-particle azimuthal correlations in photo-nuclear ultra-peripheral Pb+Pb collisions at 5.02~TeV with ATLAS

The ultra-peripheral collisions (UPCs) of relativistic heavy ion beams lead to a diverse set of photon-nucleus interactions. The measurements of particles and their interaction produced in photo-nuclear reactions can shed light on the QCD dynamics of novel, extremely asymmetric colliding systems, with energies between those available at RHIC and the LHC. Understanding the hadronic fluctuation spectrum of the photon in this fashion is also critical for maximizing the precision of measurements at a future Electron Ion Collider facility. This talk presents a measurement of two-particle long-range azimuthal correlations in photo-nuclear collisions using 1.73~nb$^{-1}$ of 5.02~TeV~Pb+Pb data collected in 2018 by ATLAS with a dedicated photo-nuclear event trigger. Candidate photo-nuclear events are selected using a combination of the single-sided zero-degree calorimeter activity and reconstructed pseudorapidity gaps constructed from calorimeter clusters and charged-particle tracks. Correlation functions are constructed using charged-particle tracks, separated in pseudorapidity. A template fitting procedure is utilized to subtract the non-flow contribution. Elliptic and triangular flow coefficients are presented as a function of charged-particle multiplicity and transverse momentum, and significant non-zero values of the flow coefficients are observed. The results are compared to flow coefficients obtained in $pp$ and $p$+Pb collisions in similar multiplicity ranges.

Speaker: Blair Seidlitz

BSeidlitz_EPSHEP_FINAL.pdf

T06: QCD and Hadronic Physics: Part 8: Low-energy phenomena

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Ferenc Siklér (Wigner RCP, Budapest)

546 Recent result of nucleon time-like form factors at BESIII

Nucleons are one of the most fundamental building blocks of ordinary matter, yet their internal structure and dynamics are still not fully understood. Electromagnetic form factors allow to investigate fundamental properties of the nucleon. The BESIII collaboration has studied the time-like form factors of the proton using the energy scan and the ISR technique. The |GE/GM| ratio is obtained with a precision comparable to the investigations of the space-like EMFF in electron proton scattering. The effective form factor of the neutron is measured with highest precision using the scan method. For both nucleons, an intriguing periodic behavior of effective form factors lineshape is observed. In this presentation the latest results on nucleon form factors at BESIII are discussed.

Speaker: Dr Marco Destefanis (University of Torino and INFN)

Destefanis_eps_20210726.pdf

547 Simultaneous extraction of fragmentation functions of light charged hadrons with mass corrections

We describe a simultaneous determination of unpolarized FFs of charged pions, charged kaons, and protons/antiprotons from single-inclusive hadron production in electron-positron annihilation (SIA) data at next-to-leading order and next-to-next-to-leading order accuracy in perturbative QCD. We include data for identified light charged hadrons as well as for unidentified light charged hadrons, and show that these data have a significant impact on both size and uncertainties of the fragmentation functions. We examine the inclusion of higher-order perturbative QCD corrections and finite-mass effects. We compare the new SGKS20 FFs with other recent FFs available in the literature and find in general reasonable agreement, but also important differences for some parton species. We show that theoretical predictions obtained from our new FFs are in very good agreement with the analyzed SIA data, especially at small values of z.

Speaker: Maryam Soleymaninia (IPM)

EPS-HEP2021-M.Soleymaninia copy.pdf

548 Low-mass dielectron measurements with ALICE at the LHC

Dileptons and photons are unique tools to study the space–time evolution of systems created by QCD in hadronic collisions. They are produced continuously by a variety of sources, in particular prompt and thermal photons and semileptonic heavy-flavour hadron decays, during the entire history of the collision and traverse the medium with negligible final state interaction. So they can carry undistorted information on early stages of the collision.
In this contribution, we will present results from the recent measurements of e$^{+}$e$^{-}$ pair production in pp and p--Pb collisions at the center-of-mass energy $\sqrt{s_{\rm NN}}$ = 5.02 TeV. Charm and beauty cross sections are extracted to investigate possible cold nuclear matter effects such as shadowing by comparing different nPDFs on the nuclear modification factor $R_{\rm pPb}$.
Furthermore, our results on dielectrons at low $p_{\rm T,ee}$ in pp collisions at $\sqrt{s}$ = 13 TeV and new preliminary results of dilepton production from photoproduction in inelastic Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV are presented and compared to expectations from calculations including bremsstrahlung (for pp collisions) and photoproduction (for Pb-Pb collisions).

Speaker: Hermann Degenhardt

LMee_ALICE_EPS.pdf

549 Hadron physics at KLOE/KLOE-2, results and perspectives (12'+3')

The KLOE-2 experiment, at the $e^+e^-$ DA$\Phi$NE collider in Frascati, acquired an integrated luminosity of about 5 fb$^{-1}$ with an upgraded KLOE apparatus. The whole KLOE/KLOE-2 data sample corresponds to 2.4 $\times 10^{10} \,\phi$ and $3.1 \times 10^8 \,\eta$ meson events allowing to develop a wide hadron physics program from rare meson decays to $\gamma\gamma$ fusion and dark forces.

KLOE-2 investigates the $\eta \to \pi^0 \gamma \gamma$ decay, an important test of ChPT because of its sensitivity to the $p^6$ term on both the branching ratio and the M($\gamma\gamma$) spectrum. A preliminary KLOE measurement, based on 450 pb$^{-1}$, provided a 4 sigma's lower value w.r.t. the most accurate determination of the BR from the Crystal Ball experiment. The new KLOE measurement performed with a larger data sample statistics will be presented.
By using the same five photon final state and
following the many KLOE-2 contributions to Dark Matter (DM) searches, an alternative model, where the dark force mediator is an hypothetical leptophobic B boson, is exploited in the $\phi$ decay to $\eta$-B where B will decay in $\pi^0\gamma$.

Moreover, KLOE-2 has the possibility to investigate $\pi^0$ production from $\gamma \gamma$ fusion thanks to two scintillator hodoscopes installed in the DA$\Phi$NE beam pipe to tag final-state leptons from $e^+e^- \to \gamma^{\ast}\gamma^{\ast}e^+e^-\to \pi^0 e^+e^-$ . The aim is to perform the high precision measurement of the $\pi^0$ width to test low-energy QCD dynamics. The status of the $\gamma^{\ast}\gamma^{\ast}\to \pi^0$ analysis will be reported.

KLOE-2 searches also the
$\phi\rightarrow \eta\, \pi^+ \pi^- ,\,\mu^+\mu^-$ decays with $\eta\rightarrow\gamma \gamma$ and $\eta \to 3\pi^0$. $\phi\rightarrow \eta \pi^+ \pi^- $ is double suppressed by G−parity and the OZI rule, with an expected BR around $0.35\times 10^{−6}$, while for the $\phi\rightarrow \eta \mu^+\mu^-$ decay an upper limit was set as $0.94\times10^{−5}$. By analyzing those decays with KLOE/KLOE-2 data clear signals are seen for the first time.

Speaker: Cao Bo (Uppsala University)

eps2021.pdf

550 Beauty-hadron spectroscopy at LHCb (12'+3')

The spectroscopy of conventional hadrons containing a beauty quark is crucial to improve the knowledge of the non-perturbative regime of QCD. The LHCb experiment has been designed to study such hadrons and it is the ideal laboratory to search for as-yet-unobserved beauty baryons, including double heavy hadrons, and to perform precision measurements of already established hadrons. This talk presents the corresponding recent results performed at LHCb.

Speaker: Hongjie Mu (Tsinghua)

eps_report.pdf

551 Double parton scattering and exclusive hadron productions in CMS

Double parton scattering (DPS) is investigated using a states of a Z boson and jets, and of four jets, with CMS proton collisions data at 13 TeV. Final state distributions are studied as functions of several observables that exploit correlations between the jets, and the Z boson, with sensitivity to different aspects of the underlying event, parton shower, and matrix element calculations. Values of the effective DPS cross section are calculated and discussed. The central exclusive production of charged hadron pairs in pp collisions at a center- of-mass energy of 13 TeV is also examined with the CMS experiment. Differential cross sections as functions of the polar scattering angle of the incoming protons and several squared four-momenta are measured in a wide region of scattered proton transverse momenta. The dynamics of nonresonant continuum is determined and compared to models.

Speaker: Maxim Pieters (CERM-CMS)

DPSatCMS_EPS2021_revised.pdf

T07: Top and Electroweak Physics: Part 5

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Elisabetta Gallo-Voss (CMS (CMS-Experiment)), William Barter (Imperial College London)

552 Interplay of beam polarisation and systematic uncertainties at future e+e- colliders

Future high-energy $e^{+}e^{-}$ colliders will provide some of the most precise tests of the Standard Model. Statistical uncertainties on electroweak precision observables and triple gauge couplings are expected to improve by orders of magnitude over current measurements.

This provides a new challenge in accurately assessing and minimising the impact of systematic uncertainties. Beam polarisation may hold a unique potential to isolate and determine the size of systematic effects. So far, studies have mainly focused on the statistical improvements from beam polarisation. This study aims to assess, for the first time, its impact on systematic uncertainties.

A combined fit of precision observables, such as chiral fermion couplings and anomalous triple gauge couplings, together with experimental systematic effects is performed on generator-level differential distribution of 2-fermion and 4-fermion final-states. Different configurations of available beam polarisations and luminosities are tested with and without systematic effects, and will be discussed in the context of the existing projections on fermion and gauge boson couplings from detailed experimental simulations.

Speaker: Jakob Beyer (FLC (FTX Fachgruppe SLB))

2021_07_29_EPS_HEP.pdf

553 Precision electroweak measurements at the LHeC and the FCC-he

The measurements of inclusive deep-inelastic electron-proton scattering (DIS) cross sections at high center-or-mass energies offer a unique opportunity for precision tests of electroweak interactions. In this talk we revisit electroweak effects in DIS and discuss the combined determination of parameters of electroweak theory together with parton distribution functions of the proton [1,2]. Using simlulated data for the future DIS experiments LHeC and FCC-he, we study the determination of the W, Z and top-quark mass from inclusive measurements. We will show the possibilities for the determination of the vector and axial couplings of light quarks, and outline a unique measurement of the running the effective weak mixing angle. The sensitivity of future inclusive DIS data to generic extensions of the electroweak standard model is further investigated.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e-Print: 2007.14491 [hep-ex], to appear in J. Phys. G.
[2] Daniel Britzger, Max Klein, Hubert Spiesberger, Eur.Phys.J.C 80 (2020) 9, 831, e-Print: 2007.11799 [hep-ph].

Speaker: Daniel Britzger (Max-Planck-Institut für Physik, München)

210729-britzger-LHeC-EW.pdf

554 New electroweak challenges and opportunities at the LHeC

The Large Hadron-Electron Collider (LHeC) will operate at √s = 1.2 TeV and accumulate about 1/ab of integrated electron-proton luminosity [1]. We report here results of a novel study of high energy photon-photon interactions at the LHeC, at the 𝛾𝛾 center-of-mass energy of up to 1 TeV, opening new frontiers in the electroweak physics. Despite very high ep luminosity, the experimental conditions will be very favorable at the LHeC – a negligible event pileup will allow for unique studies of exclusive production via two-photon fusion. We discuss a number of such processes, as 𝛾𝛾 → WW for example, including estimates of their principal backgrounds. We conclude by evaluating the impact of measurements at the LHeC of such two-photon interactions on testing of the electroweak sector of Standard Model and searches for physics beyond the SM.

[1] P. Agostini et al. (LHeC Study Group), The Large Hadron-Electron Collider at the HL-LHC, accepted by J. Phys. G; https://arxiv.org/abs/2007.14491.

Speaker: Krzysztof Piotrzkowski (UCLouvain)

EPS_KPv1.3.pdf

555 Photon-photon fusion measurements at ATLAS

Photon-photon fusion is a rare process at hadron and ion colliders. It is particularly interesting as a remarkably clean interaction with little (if any) remnant activity from the interacting particles. In this talk we present the status of photon-photon fusion measurements at the ATLAS detector. We present differential measurements of the light-by-light scattering process, γγ → γγ, in lead-lead collisions. In addition, we present photon-photon fusion measurements that contain two charged leptons in the final state. The scattered proton is detected by the ATLAS Forward Proton spectrometer while the leptons are reconstructed by the central ATLAS detector. Finally, we highlight the observation of photon-induced WW production.

Speaker: Savannah Clawson (University of Manchester)

ATLAS_photon_fusion_EPSHEP2021.pdf

T09: Higgs Physics: Prospects - part 2

Conveners: Sarah Heim (DESY), Giovanni Marchiori (APC Paris - CNRS/IN2P3 and Université de Paris), Michael Trott (NBI), meng xiao (zhejiang university)

556 Electron Yukawa from s-channel resonant Higgs production at FCC-ee

Measuring the electron Yukawa is impossible in Higgs boson decays, H -> e+e- , given the smallness of the electron mass that leads to a vanishingly small decay branching fraction. The only direct method to extract the Higgs-electron coupling is through resonant s-channel production in e+e- collisions running at the Higgs pole mass. Such a measurement is possible at the FCC-ee provided one can monochromatize the beams, leading to a center-of-mass energy spread not much larger than the Higgs boson width of ~4 MeV, as well as having a prior accurate and precise knowledge of the Higgs boson mass, within MeV uncertainties. Under such conditions, a study combining 10 different Higgs decay modes indicates that a ~1.3sigma significance for the e+e- -> H process can be reached, above the (much larger) backgrounds, for every 10 ab-1 of integrated luminosity per FCC-ee interaction point (IP). Depending on the number of IPs and years running at the Higgs pole, such a measurement will provide the only means known to access the electron Yukawa.

Speaker: Mr David d'Enterria (CERN)

dde_ee_Higgs_schannel_fcc_hep_eps_desy_jul21.pdf

557 Higgs physics at the LHeC and the FCC-he

Higgs production cross sections at LHeC (FCC-he) energies are as large (larger than) those at future Z-H $e^+e^-$ colliders. This provides alternative and complementary ways to obtain very precise measurements of the Higgs couplings, primarily from luminous, charged current DIS. Recent results for LHeC and FCC-he [1] are shown and their combination is presented with pp (HL-LHC) cross sections leading to precision comparable to the most promising $e^+e^-$ colliders. We will show the results for the determination of several signal strengths and couplings to quarks, leptons and EW bosons, and discuss the possibilities for measuring the coupling to top quarks and its CP phase, and the search for invisible decays.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e-Print: 2007.14491 [hep-ex], to appear in J. Phys. G.

Speaker: Uta Klein (ZEUS (ZEUS Experiment))

EPS2021_29.07.2021.pdf

558 Higgs boson couplings at muon collider

Muon collisions at multi-TeV center of mass energies are ideal for studying Higgs boson properties. At these energies the production rates will allow precise measurements of its couplings to fermions and bosons. In addition the double Higgs boson production rate could be sufficiently high to directly measure the parameters of trilinear self-couplings, giving access to the determination of the Higgs potential.
This contribution aims to give an overview of the results that have been obtained so far on Higgs couplings by studying the $\mu^+ \mu^- \to H \nu \bar{\nu}$ and $\mu^+ \mu^- \to HH \nu \bar{\nu}$ processes. All the studies have been performed by fully simulating the signal and physics background samples and by evaluating the effects of the beam-induced background on the detector performances.
Evaluations on Higgs boson couplings sensitivities and most recent results on the uncertainty on double Higgs production cross section, together with the trilinear self-coupling, will be discussed at $\sqrt{s}$ of 3 TeV and extrapolated to 10 TeV.

Speaker: Laura Buonincontri (INFN & Università degli Studi di Padova)

slide_eps_LB.pdf

T12: Detector R&D and Data Handling: Reconstruction

Conveners: Vincent Boudry (LLR – École polytechnique), Magnus Mager (CERN)

559 Application of Quantum Machine Learning to High Energy Physics Analysis at LHC Using Quantum Computer Simulators and Quantum Computer Hardware

Machine learning enjoys widespread success in High Energy Physics (HEP) analysis at LHC. However the ambitious HL-LHC program will require much more computing resources in the next two decades. Quantum computing may offer speed-up for HEP physics analysis at HL-LHC, and can be a new computational paradigm for big data analysis in High Energy Physics.

We have successfully employed Variational Quantum Classifier (VQC) method, Quantum Support Vector Machine Kernel (QSVM-kernel) method and Quantum Neural Network (QNN) method for two LHC flagship analyses: ttH (Higgs production in association with two top quarks) and H->mumu (Higgs decay to two muons, the second generation fermions).

We will present our experiences and results of a study on LHC High Energy Physics data analysis with IBM Quantum Simulator and Quantum Hardware (using IBM Qiskit framework), Google Quantum Simulator (using Google Cirq framework), and Amazon Quantum Simulator (using Amazon Braket cloud service). The work is in the context of a Qubit platform. Taking into account the present limitation of hardware access, different quantum machine learning methods are studied on simulators and the results are compared with classical machine learning methods (BDT, classical Support Vector Machine and classical Neural Network). Furthermore, we do apply quantum machine learning on IBM quantum hardware to compare performance between quantum simulator and quantum hardware.

The work is performed by an international and interdisciplinary collaboration with the Department of Physics and Department of Computer Sciences of University of Wisconsin, CERN Quantum Technology Initiative, IBM Research Zurich, Fermilab Quantum Institute, BNL Computational Science Initiative, State University of New York at Stony Brook, and Quantum Computing and AI Research of Amazon Web Services.

This work pioneers a close collaboration of academic institutions with industrial corporations in a High Energy Physics analysis effort.

Although the era of efficient quantum computing may still be years away, we have made promising progress and obtained preliminary results in applying quantum machine learning to High Energy Physics. A PROOF OF PRINCIPLE.

Speaker: Sau Lan Wu (University of Wisconsin-Madison)

SLW_QuantHEP talk for EPS-HEP 2021.pdf

560 Recent advancements in high-performance analysis and statistical modelling with ROOT

ROOT is renovating itself at a fast pace in order to allow physicists to address the unprecedented scale of LHC Run 3 datasets and beyond. Thanks to these recent developments, many HEP analyses could be made 5 to 20 times faster, providing turnaround times in the order of minutes rather than hours.

ROOT's RDataFrame, a high-level interface for data analysis and processing in C++ and Python, provides an ergonomic entry point to many of these improvements. It transparently leverages the power of modern multi- and many-core hardware; its declarative design makes it a robust and simple tool to efficiently pipe ROOT data into standard machine learning frameworks; distributed processing is enabled via ad-hoc back-ends capable to connect, for example, to existing Spark or Dask clusters, also enabling scalable deployment on HPC resources.
At the same time RooFit, ROOT's statistical modelling framework, is being upgraded in order to provide state-of-the-art performance on modern CPUs and GPUs.

This contribution will present recent advancements in these areas as well as upcoming enhancements that will make ROOT easier to use, faster out of the box, and adaptable to future workflows.

Speaker: Enrico Guiraud (EP-SFT, CERN)

ROOT @ EPS-HEP.pdf

561 The Key4hep turnkey software stack for future colliders

Detector optimisation and physics performance studies are an integral part for the development of future collider experiments.
The Key4hep project aims at providing a common stack of easy to use software tools for future, or even present, High Energy Physics projects. Key4hep is to a large extent based on software tools that are already very actively used in the community like ROOT, Geant4 and DD4hep or those that are currently under active development like EDM4hep or ACTS. The Key4hep project is, among others, supported by the HEP Software Foundation, CERN, DESY and the AIDAinnova project and has active developers from all large future collider projects: CEPC, CLIC, FCC, and ILC.
In this talk we present an overview on the Key4hep project and describe the ongoing adaptation processes of the different future experiments, thereby showing that Key4hep is a viable long term solution as baseline software for high energy experiments that will facilitate the scientific exchange between these communities in the coming years.

Speaker: Placido Fernandez Declara (CERN)

placido_key4hep_eps-hep2021.pdf

562 Exploring the structure of hadronic showers and the hadronic energy reconstruction with highly granular calorimeters

Prototypes of electromagnetic and hadronic imaging calorimeters developed and operated by the CALICE collaboration provide an unprecedented wealth of highly granular data of hadronic showers for a variety of active sensor elements and different absorber materials. In this presentation, we discuss detailed measurements of the spatial and the time structure of hadronic showers to characterise the different stages of hadronic cascades in the calorimeters, which are then confronted with GEANT4-based simulations using different hadronic physics models. These studies also extend to the two different absorber materials, steel and tungsten, used in the prototypes. The high granularity of the detectors is exploited in the reconstruction of hadronic energy, both in individual detectors and combined electromagnetic and hadronic systems, making use of software compensation and semi-digital energy reconstruction. The results include new simulation studies that predict the reliable operation of granular calorimeters. Further we show how granularity and the application of multivariate analysis algorithms enable the separation of close-by particles. We will report on the performance of these reconstruction techniques for different electromagnetic and hadronic calorimeters, with silicon, scintillator and gaseous active elements.

Speaker: Vladimir Bocharnikov (LPI, DESY)

VB_EPS-HEP21.pdf

T13 - Accelerator for HEP: Part 3

563 The SHERPA experiment

The SHERPA (“Slow High-efficiency Extraction from Ring Positron Accelerator”) project aim is to develop an efficient technique to extract a positron beam from one of the accelerator rings composing the DAΦNE accelerator complex at the Frascati National Laboratory of INFN, setting up a new beam line able to deliver positron spills of O(ms) length, excellent beam energy spread and emittance.
The most common approach to slowly extract from a ring is to increase betatron oscillations approaching a tune resonance in order to gradually eject particles from the circulating beam.
SHERPA proposes a paradigm change using coherent processes in bent crystals to kick out positrons from the ring, a cheaper and less complex alternative [1]. This non-resonant technique, already successfully used and still developed mainly in hadron accelerators, will provide a continuous multi-turn extraction of a high quality beam [2, 3, 4, 5].
Realizing this for sub-GeV leptons is challenging, however would provide the world’s first primary positron beam obtained with crystal extraction. An immediate application of this new extracted beam line would be the PADME (“Positron Annihilation into Dark Matter Experiment”) experiment [6], currently strongly limited by the duty cycle. Using the proposed extraction, PADME could increase the statistics by a factor 10^4 and its sensitivity by a factor 10^2.
This technology can be applied in general for both negative and positive leptons, including muons, providing a know how that can be applied for several accelerating machine aspects in the next future, as collimation, extraction and beam splitting, contributing to a general improvement in the particle accelerator field.
In the talk will be given an overview of the whole experiment, describing in particular the crystal extraction principle, the accelerator optics studies, the crystal prototype and the characterization apparatus. First simulation and experimental results will be reported.

References:
. [1] M. Biryukov et al, Crystal channeling and its application at high-energy accelerators. Springer Science Business Media, 2013 
17 

. [2] X. Altuna et al, Phis. Lett. B 357 (1995) 671-677 

. [3] A.G. Afonin et al, Phys. Rev. Lett. 87, 094802 (2001) 

. [4] W. Scandale et al, Phys. Lett. B 758 (2016) 129-133 

. [5] M.A. Fraser et al, 8th IPAC, Copenhagen (2017) 

. [6] M. Raggi et al, EPJ Web Conf. 142 (2017) 01026

Speaker: Marco Garattini (INFN-LNF)

SHERPAtalk_EPS-HEP2021.pptx

564 Measurement of the muon precession frequency in magnetic field for the measurement of the muon magnetic anomaly

The FNAL Muon g-2 collaboration has performed a measurement of the muon magnetic anomaly to 0.46 ppm, based on the ratio between the observed spin precession frequencies of orbiting positive muons to protons at rest in the same magnetic field. We describe how the muon precession frequency has been measured by fitting the modulation of the rate of high energy positrons detected by the experiment calorimeters. The muon precession measurement has been performed in a blind way, with 11 analyses performed by 6 independent groups, employing comprehensive fit models with up to 25 fit parameters. Additional studies have been completed to estimate several systematic uncertainties due to the detector response. statistical uncertainty of 0.43 ppm has been obtained using about 8.2 billion muon decays recorded at FNAL in 2018, while the systematic uncertainty has been estimated to be 0.06 ppm.

Speaker: Alberto Lusiani (Scuola Normale Superiore and INFN, sezione di Pisa)

alusiani-eps21.pdf

565 High-quality beams from a high-efficiency plasma accelerator at DESY’s FLASHForward facility, and beyond

Plasma accelerators can drastically shrink large-scale future accelerator facilities such as a linear collider. Maintaining high beam quality and accelerating with high energy efficiency is key to delivering high luminosity per wall-plug power. However, this is particularly challenging in a plasma accelerator due to their microscopic size—extreme precision and stability is required. We present recent results from DESY’s FLASHForward plasma-accelerator facility, showing preserved energy spread and charge while accelerating with GV/m gradients at record efficiency and stability. Moreover, a new concept for self-correcting plasma acceleration is presented, which may provide orders of magnitude better beam quality and stability for applications in the future.

Speaker: Dr Carl A. Lindstrøm (FTX AST)

High-quality beams from a high-efficiency plasma accelerator at DESY’s FLASHForward facility, and beyond (EPS-HEP 2021).pdf

T14: Outreach, Education and Diversity: Part 4

566 LA-CoNGA physics: an open science education collaboration between Latin America and Europe for High Energy Physics

The communities of astrophysics, astronomers and high energy physicists have been pioneers in establishing Virtual Research and Learning Networks (VRLCs)[1] generating international productive consortiums in virtual research environments and forming the new generation of scientists. In this talk we will discuss one in particular: LA-CoNGA Physics (Latin American alliance for Capacity buildiNG in Advance physics) [2].

LA-CoNGA physics aim to support the modernization of the university infrastructure and the pedagogical offer in advanced physics in four Latin American countries: Colombia, Ecuador, Peru and Venezuela. This virtual teaching and research network is composed of 3 partner universities in Europe and 8 in Latin America, high-level scientific partners (CEA, CERN, CNRS, DESY, ICTP), and several academic and industrial partners. The project is co-funded by the Education, Audiovisual and Culture Executive Agency (EACEA) of the European Commission.

Open Science education and Open Data are at the heart of our operations. In practice LA-CoNGA physics has created a set of postgraduate courses in Advanced Physics (high energy physics and complex systems) that are common and inter-institutional, supported by the installation of interconnected instrumentation laboratories and an open e-learning platform. This program is inserted as a specialization in the Physics masters of the 8 Latinamerican partners in Colombia, Ecuador, Peru and Venezuela. It is based on three pillars: courses in high energy physics theory/phenomenology, data science and instrumentation.

In the current context, VRLCs and e-learning platforms are contributing to solve challenges, such as distance education during the COVID19 pandemic.

[1] http://www.oecd.org/sti/inno/international-distributed-research-infrastructures.pdf
[2] http://laconga.redclara.net

Speaker: Jesús Peña-Rodríguez (Universidad Industrial de Santander)

LA-CoNGAphysics_EPS2021.pdf

567 AIMS, a few actions and their impact

The African Institute for Mathematical Sciences is a network of excellence centres
for innovative post-graduate training in mathematical sciences in Africa.
Established in 2003, today AIMS counts 6 institutes in 5 African countries
(Cameroon, Ghana, Rwanda, Senegal, South Africa) and focuses on academics,
research, and industry initiative. The students at AIMS follow different academic
cursus (mathematical sciences, co-operative education program,
climate sciences, machine learning and intelligence). I will present a few actions
and the impact that this prominent education network has on the scientific life
of some African students.

Speaker: Joseph Ben Geloun (Universté Sorbonne Paris Nord)

AIMS_talk_submitted.pdf

568 The IPPOG resource database: particle physics reaching out globally

The International Particle Physics Outreach Group (IPPOG) has been making concerted and systematic efforts to present and popularize particle physics across all audiences and age groups since almost 25 years. Today the scientific community has in IPPOG a strategic pillar in fostering long-term, sustainable support for fundamental research around the world. One of the main tools IPPOG has been offering to the scientific community, teachers and educators since almost 10 years is the Resource Database (RDB), an online platform containing the collection of high-quality engaging education and outreach materials in particle physics and related sciences. After almost 10 years, a new digital portfolio aiming to greatly broaden the audience type and strengthen the user experience, is being developed including a new RDB, which is currently undergoing a major curation process in order to ensure the resources are up-to-date and of the highest quality. IPPOG wants the new website to become more open to students, teachers, and the general public and the new RDB to become the primary source of particle physics outreach material in the world, which would help to bring particle physics closer to the society.

Speaker: Dr Barbora Bruant Gulejova (IPPOG / University of Bern / CERN)

IPPOG_RDB_EPS_HEP_2021_BBG_final.pptx

569 Particle therapy masterclass

With the aim to highlight the impact of fundamental research on the broader society, the new Particle Therapy MasterClass (PTMC) package was developed and recently integrated into the International MasterClass 2021 (IMC) online programme, attracting some 37 institutes from 20 countries and more than 1500 students. The PTMC is focusing on the topic of cancer treatment, a particular sensitive topic. The main idea is to show that (a) fundamental properties of particle interactions with matter, which are used to detect them in physics experiments, are also the basis for treating cancer tumours; and (b) the same accelerator technologies are used in both research laboratories and therapy centres.
For the hands-on session, the open source professional Treatment Planning software matRad is used, developed for research and training by DKFZ, the German cancer research institute, Heidelberg.
Ultimately students are shown “what physics has to do with medicine” and what are the various possibilities that physics and STEM studies may open up for job opportunities in fields that there is lack of expert personnel.

Speaker: Dr Yiota Foka (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH)

YF-PTMC-ForEPS-29july2021-asGiven-Cropped.pptx

570 Education and outreach activities in the Extreme Energy Events Project

The Extreme Energy Events Project (EEE) is an experiment devoted to the study of Extensive Atmospheric Showers (EAS) through an array of muon telescopes. It was directly born with the intent to involve high school students and teachers in its advanced physics research. Each EEE telescope was built by students and teachers at CERN and most of the telescopes are located inside Italian school buildings where school teams help to monitor and operate the detectors. During the years the EEE project has broadened the telescopes network and its outreach program has been also enriched with new activities. Within the project a large community of researchers, teachers and hundreds of students has been formed, continuously involved in seminars arranged to introduce the young students to data analysis, in meetings to confront their ideas, problems and results, in measurements campaigns where they may also use additional small detectors and help to improve the telescopes performance.

Speaker: Maria Paola Panetta (CREF, INFN sezione di Lecce)

EPS-HEP2021_mpp_v1.pdf

Virtual Tour of DESY and UHH campus

Convener: Christian Schwanenberger (CMS (CMS Fachgruppe TOP))

Lab_Tour_zoom_0.mp4

Friday, 30 July

T01: Astroparticle and Gravitational Waves: Part 8

Convener: Walter Del Pozzo (University of Pisa)

571 Constraining alternative theories of gravity using the latest LIGO-Virgo ringdown observations

Detections of black hole mergers from the LIGO-Virgo interferometers provide an unprecedented opportunity to glance into unexplored regimes of gravity, where spacetime curvature is several orders of magnitudes larger than the one probed by other experiments. First, the state of the art of black holes ringdown spectral observations will be reviewed. Next, we will show how requiring stringent, yet well-motivated, perturbative parametrisations of beyond- General Relativity effects, allows to extract strong observational constraints on large classes of alternative theories of gravity. Such a boost brings observations close to the regime where corrections from Effective Field Theories of beyond-General Relativity gravity may start to leave a detectable imprint, and translates into a much smaller number of signals needed to detect violations due to an alternative theory of gravity. Finally, we will show what constraints can be placed on a few specific theories, where a self-consistent, non-perturbative prediction can be tested against the data.

Speaker: Gregorio Carullo (University of Pisa, INFN Pisa)

Carullo_EPS_July_2021.pdf

572 Gravitational wave echo from relaxion trapping

We show that the relaxion coupled to a dark photon can generate a stochastic gravitational wave background in the early Universe. When the electroweak symmetry is restored after reheating, the relaxion starts rolling again until the back-reaction potential wiggles reappear. Depending on the time of barrier-reappearance, Hubble friction alone is insufficient to trap the relaxion in a large portion of the parameter space. Thus, an additional source of friction is required, which can for instance be provided by coupling to a dark photon. The dark photon experiences a tachyonic instability as the relaxion rolls, which slows down the relaxion by back-reacting to its motion, and creates anisotropies in the dark photon energy-momentum tensor, sourcing gravitational waves. We calculate the spectrum of the resulting stochastic gravitational wave background and evaluate its observability by current and future experiments. We further investigate the case that the coherently oscillating relaxion constitutes dark matter and present the corresponding constraints from gravitational waves.

Speaker: Dr Eric Madge (Weizmann Institute of Science)

animation_slide_7.mp4

animation_slide_9.mp4

slides.pdf

573 Methods and results on the search for gravitational wave echoes in the post-merger phase after binary black hole coalescences.

The current Gravitational Wave (GW) surveys of Binary Black Hole (BBH) mergers provide unprecedented probes of the dynamics in extreme gravitational fields and relativistic velocities. It has been proposed that these Compact Objects may have exotic characteristics making them be different from simpler Black Holes (BHs): they would produce repeated GW pulses of widely uncertain morphology (echoes) in the post-merger phase.
We will present a method for searching echoes that is agnostic to the properties of the GW pulses and discuss its discovery potential in terms of echoes' strength. The method is based on a dedicated version of coherentWaveBurst (cWB), an unmodelled GW transient search algorithm, developed in LVC and widely used on LIGO-Virgo-KAGRA data.
The performances in terms of detection and estimation of echoes' characteristics have been investigated on actual data from past LIGO-Virgo observing runs (O1 and O2) by injecting a large set of simulated signals.
Moreover, we will present the new upper limits in echoes detection set by this search on LIGO-Virgo open data and open catalogs of detected CBC.

Speaker: Andrea Miani (Virgo)

cWB-SubTh_Search_EPS.pdf

574 Search for multi-messenger events during LIGO/Virgo era

Multi-messenger astronomy is a vast and expanding field as electromagnetic (EM) observations are no longer the only way of exploring the Universe. This field had its dawn when new astronomical messengers of non-electromagnetic origin were observed: solar flare, neutrinos, and most recently the detection of gravitational waves (GWs) in 2015. Due to these new messengers, astrophysical triggers with both GWs and EM are no longer a dream of the astronomical community. A breakthrough for GW multi-messenger astronomy came when the LIGO-Virgo network detected a GWs signal of two low-mass compact ob- jects consistent with a neutron star binary (BNS, GRB170817), an event that generated a short gamma ray burst (sGRB), and a kilonova. While GW170817 represents the testimony for BNS mergers being the progenitor of at least some GRBs, a wide range of highly energetic astrophysical phenomena is expected to be accompanied by the emission of GWs and EM. Here we present the unmod- elled method to search for GWs having gamma and radio counterparts using the LIGO/Virgo data and observations of partners’ telescopes. We also discuss the most recent results of unmodelled coherent LIGO-Virgo searches targeting astrophysical triggers during the first part of the third observing run (O3a): (i) 105 gamma-ray bursts detected by the Fermi and Swift satellites, and (ii) fast radio bursts detected by CHIME. Finally, a summary of the prospects of unmodelled burst analysis for the second part of the third observing run (O3b) will be given.

Speaker: Iara Tosta e Melo (LNS INFN - Uniss)

eps_30:07:21.pdf

575 Search for lensing signatures in the gravitational-wave observations from the first half of LIGO-Virgo's third observing run

The Advanced LIGO and Advanced Virgo detectors are now observing large numbers of gravitational-wave signals from compact binary coalescences, with 50 entries in the latest transient catalogue GWTC-2. With this rapidly growing event rate, our chances become better to detect rare astrophysical effects on these novel cosmic messengers. One such rare effect with a long and productive history in electromagnetic astronomy and great potential for the future of GW astrophysics is gravitational lensing. This presentation covers the first LIGO-Virgo collaboration search for signatures of gravitational lensing in data from O3a, the first half of the third advanced detector observing run. We study: 1) the expected rate of lensing at current detector sensitivity and the implications of a (non-)observation of strong lensing or a stochastic gravitational-wave background on the merger-rate density at high redshift; 2) how the interpretation of individual high-mass events would change if they were found to be lensed; 3) the possibility of multiple images due to strong lensing by galaxies or galaxy clusters; and 4) possible wave-optics effects due to point-mass microlenses.

Speaker: Dr David Keitel (Universitat de les Illes Balears)

20210730_EPS-HEP2021-O3aLensing_v3.pdf

576 Implications for fi rst-order cosmological phase transitions and the formation of primordial black holes from the third LIGO-Virgo observing run

We place constraints on the normalised energy density in gravitational waves from first-order strong phase transitions and then from the formation of primordial black holes using data from Advanced LIGO and Virgo's first, second and third observing runs. First, adopting a broken power law model, we place 95 % confidence level upper limits simultaneously on the gravitational-wave energy density at 25 Hz from unresolved compact binary mergers and strong first-order phase transitions. We then consider two more complex phenomenological models, limiting at 25 Hz the gravitational-wave background due to bubble collisions and the background due to sound waves at 95 % confidence level for phase transitions occurring at temperatures above 1e8 GeV. We then do a similar search assuming a background sourced by the formation of primordial black holes and unresolved compact binary mergers. For a very generic spectrum describing the primordial black hole background, we place 95% confidence level upper limits on the gravitational-wave energy density at 25 Hz

Speaker: Alba Romero-Rodríguez (IFAE)

EPS-HEP2021.pdf

T03: Dark Matter: Part 7

Conveners: Belina von Krosigk (Universität Hamburg), Laura Lopez-Honorez (Universite Libre de Bruxelles)

577 B anomalies and muon g-2 from Dark Matter

In the light of the recent result of the Muon g-2 experiment and the update on the test of lepton flavour universality R_K published by the LHCb collaboration, we systematically build and discuss a set of models with minimal field content that can simultaneously give: (i) a thermal Dark Matter candidate; (ii) large loop contributions to b→sℓℓ processes able to address R_K and the other B anomalies; (iii) a natural solution to the muon g−2 discrepancy through chirally-enhanced contributions.

Speaker: Lorenzo Calibbi (Nankai University)

calibbi-eps-hep21.pdf

578 Dark Matter Searches at Belle II, Belle, and BaBar

The Belle II experiment at the asymmetric $e^+e^-$ collider, SuperKEKB, is a substantial upgrade of the Belle/KEKB experiment. Belle II aims to record 50 ab$^{-1}$ of data over the course of the project. During the first physics runs in 2018-2020, around 100 fb$^{-1}$ of data were collected. These early data include specifically-designed low-multiplicity triggers which allow a variety of searches for light dark matter and dark-sector mediators in the GeV mass range.

This talk will present the very first world-leading physics results from Belle II: searches for the invisible decays of a new vector Z’, and visible decays of an axion-like particle; as well as the near-term prospects for other dark-sector searches. Many of these searches are competitive with the data already collected or the data expected in the next few years of operation. In this talk we also review the latest dark sector results from the first generation of B factories: BaBar and Belle.

Speaker: Marcello Campajola (INFN Napoli)

CAMPAJOLA_EPS.pdf

579 Search for self-interacting dark matter with the BABAR detector

A new class of dark matter models introduces a dark sector with new Dirac fermions charged under an additional U(1) gauge group. The corresponding gauge boson, the dark photon $A'$, has a MeV-GeV mass and couples to the Standard Model photon (and Z) via kinetic mixing. Fermionic bound states ("darkonium" $\Upsilon_D$) could form if the dark sector coupling constant is strong enough. We present a search for dark sector bound states ($\Upsilon_D$) in $e^{+}e^{-}\to \gamma \Upsilon_{D}$, $\Upsilon_{D}\to A'A'A'$, $A'\to X^{+}X^{-}$ $(X=e, \mu, \pi)$ decays for $0.02~\text{GeV} \leq m_{A'} \leq 1.0~\text{GeV}$, $1~\text{GeV} \leq m_{\Upsilon_D} \leq 10~\text{GeV}$ using the full data sample collected by the $BABAR$ detector.

Speaker: Prof. Gerald Eigen (University of Bergen)

EPS-HH.pdf

580 Dark matter searches at LHCb

The LHCb detector at the LHC offers unique coverage of forward rapidities. The detector also has a flexible trigger that enables low-mass states to be recorded with high efficiency, and a precision vertex detector that enables excellent separation of primary interactions from secondary decays. This allows LHCb to make significant (and world-leading) contributions in these regions of phase space in the search for dark matter candidates, such as dark photons, hidden-sector particles, and dark matter candidates produced from heavy-flavour decays. A selection of results from these searches will be presented, alongside the potential for future measurements in these final states.

Speaker: Titus Mombächer

EPSHEP_2021_Vf.pdf

581 Search for a Dark Photon with the PADME experiment

In spite of the variety of attempts to create dark matter at accelerators, up-to-now, none of the conducted experiments has produced any evidence.
This elusiveness of dark-matter has then triggered innovative and open-minded approaches spanning a wide range of energies with high-sensitivity detectors [1].
In this scenario is inserted the Positron Annihilation into Dark Matter Experiment (PADME) ongoing at the Laboratori Nazionali di Frascati of INFN. PADME is searching a Dark Photon signal [2] by studying the missing-mass spectrum of single photon final states resulting from positron annihilation events on the electrons of a fixed target. Actually, the PADME approach allows to look for any new particle produced in e$^+$e$^−$ collisions through a virtual off-shell photon such as long lived Axion-Like-Particles (ALPs), proto-phobic X bosons, Dark Higgs ...
After the detector commissioning and the beam-line optimization, PADME collaboration collected in 2020 about $5\times10^{12}$ positrons on target at 430 MeV. These data are now under study in order to tune all analysis tools.
In the talk, it will be given an overview of the scientific program of the experiment and the performance of the detector will be presented showing Standard Model channels study ($\gamma\gamma$ events, Bremsstrahlung).

References
[1] M. Battaglieri et al., e-Print: 1707.04591 [hep-ph].
[2] M. Raggi and V. Kozhuharov, Adv. High Energy Phys. 509, (2014) 959802.

Speaker: Stefania Spagnolo (INFN Lecce and Universita' del Salento Dip. di Matematica e Fisica)

PADME-eps-hep2021-sspagnolo.pdf

582 The NA64 experiment searching for hidden sectors at the CERN SPS

NA64 is a fixed target experiment searching for hidden sectors at the CERN SPS. The experiment looks for new particles such as dark photons, axion-like particles, new light X or Z’ bosons by colliding 100-150 GeV energy electron beams onto an active target.

We will present the latest NA64 results and conclude with the future prospects of the experiment which will resume data taking this Summer after the 2 years CERN long shutdown.

Speaker: Paolo Crivelli

Crivelli-NA64_eps_hep2021.pdf

T04: Neutrino Physics: R&D projects and neutrino cross sections

Convener: Justyna Lagoda (NCBJ)

583 Theia: an advanced optical neutrino detector

Theia is a proposed large-scale novel neutrino detector, designed with the ability to discriminate between Cherenkov and scintillation signals. The design consists of a cylindrical tank viewed by inward-looking PMTs and filled with a novel target, such as water based liquid scintillator (WbLS) or other scintillator, which would allow simultaneous reconstruction of particle direction from the Cherenkov signal, with the energy resolution and low threshold of a scintillator detector. Theia would have a broad physics program ranging from low energy solar to high energy accelerator neutrinos.
In this presentation I will give an overview of the experiment based on a 100kT cylindrical tank filled with WbLS, and its physics sensitivity to various scenarios. I will also discuss a 25kT letterbox Theia detector located in a cavern similar to those under construction for DUNE, at SURF.

Speaker: Stephane Zsoldos (UC Berkeley)

2021_07_30_Stephane_ZSOLDOS_EPS-HEP.pdf

584 ProtoDUNE Physics and Results

ProtoDUNE-SP and ProtoDUNE-DP are large-scale single-phase and dual-phase prototypes of DUNEs far detector modules, operated at the CERN Neutrino Platform.   ProtoDUNE-SP has finished its Phase-1 running in 2020 and has successfully collected test beam and cosmic ray data. In this talk, we will discuss the first results of ProtoDUNE-SP Phase-1's physics performance, ProtoDUNE-DPs design and progress and future ProtoDUNE plans.

Speaker: Leigh Whitehead (University of Cambridge)

lhw_protodune_EPS_30_07_21.pdf

585 The SuperChooz Pathfinder Exploration

A new opportunity for a possible flagship experiment in Europe opens by exploiting a unique opportunity that has long been hidden in the Chooz site — Europe’s most famous site for reactor neutrino science. The “SuperChooz” project benefits by existence of 2 caverns, formerly hosting the Chooz-A nuclear reactor, built in the 60’s, that are becoming vacant upon its dismantling completion. They hold a total volume of up to 50 000m^3, thus directly comparable to the size of SuperKamiokande. Its potential use for for science purposes is under active discussion with EDF and dedicated agreement has just been signed, thus starting the official pathfinder exploration era. The SuperChooz caverns combined with the existing ~1km baseline of the most powerful 2x N4 Chooz PWR nuclear reactors make this site a unique asset world-wide. Experimentally, the challenge is the poor overburden (order 100m underground). However, the novel LiquidO technology, born as byproduct of Double Chooz, heralds the potential for unprecedented active background rejection of up to 2 orders of magnitude, thus providing feasibility potential ground for a hypothetical SuperChooz. The rationale of the experiment will be highlighted in the talk for the first time — first official released. The project is aimed to address some of the most fundamental symmetries (studies under completion) behind the Standard Model, including a design that may open for key synergies that may boost the sensitivities of other neutrino flagship experiments such as DUNE (US), JUNO (China) and HyperKamiokande (Japan).

Speaker: Anatael Cabrera (CNRS/IN2P3 IJCLab(Orsay) / LNCA (Chooz))

586 T2K latest results on neutrino-nucleus cross sections

A detailed understanding of neutrino(ν)-nucleus interactions is essential for the precise measurement of neutrino oscillations at long baseline experiments, such as T2K. The T2K near detector complex, designed to constrain the T2K flux and cross section models, also provides a complementary program of neutrino interaction cross-section measurements. Through the use of multiple target materials (carbon, water, argon, iron, lead), and the ability to sample different neutrino spectra (with detectors located on- and off-axis with respected to the flux), T2K is able to investigate atomic number and energy dependence of interaction cross sections in single experiment. An overview of the T2K measurement strategy, adopted to reduce the model dependence, and the most recent results, as well as future planned analyses, will be presented.

Speaker: Katarzyna Kowalik

EPSHEP-Xsec-KKowalik.pdf

587 An Intermediate Water Cherenkov Detector for Hyper-Kamiokande Using the NuPRISM Concept

The Hyper-Kamiokande (HK) experiment will detect neutrinos produced at an upgraded 1.3 MW J-PARC 30 GeV accelerator with a new water Cherenkov detector that is 8 times larger than Super-Kamiokande. This will allow HK to accumulate neutrino events 20 times faster than the currently operating T2K experiment. To take advantage of the high statistics HK will collect, systematic uncertainties on neutrino production and interaction modelling must be reduced. The Intermediate Water Cherenkov Detector (IWCD) is a 1 kiloton scale water Cherenkov detector to be located ~1 km from the neutrino source at J-PARC to study neutrino production and interactions. The IWCD has the unique feature that it can be moved to different positions relative the beam direction, enabling measurements that probe the relationship between neutrino energy and particles produced in neutrino interactions. I will describe the IWCD design, measurement program and the key technologies that will be deployed in the detector.

Speaker: Mark Hartz (TRIUMF/Kavli IPMU (WPI), The University of Tokyo)

iwcd_epshep_mhartz.pdf

588 QED corrections to neutrino nucleus scattering

As neutrino physics marches towards its goal of percent-level determinations of oscillation parameters, the corresponding theory of neutrinos scattering off nuclei (detector material) must be improved and developed to a sub-percent level of precision. Large logarithms, e.g. $\log(E_\nu/m_e)$, and coherent enhancements, i.e. $Z\alpha/v$, can enhance QED corrections significantly. In this talk I will discuss Coulomb corrections in detail and comment on the importance of radiative corrections for coherent elastic neutrino nucleus scattering (CEvNS).

Speaker: Ryan Plestid (University of Kentucky/Fermilab)

EPS-2021.pdf

T06: QCD and Hadronic Physics: Part 9: Precision calculations

Note: All contributions are given 12 minutes + 3 min for questions

Convener: Zoltan Nagy (T (Phenomenology))

589 ITMD factorization and its applications

I would like to review recently introduced factorization called Improved Transverse Momentum Dependent factorization which applies in the regime of QCD when the saturation effects become relevant and when one has hard final state. Furthermore I would like to present an application of this formalism to phenomenological predictions of jet production in pA and eA.

Speaker: Krzysztof Kutak (Institute of Nuclear Physics Polish Academy of Sciences)

HEP-EPS.pdf

590 Renormalization of the flavor-singlet axial-vector current and its anomaly at $N^3LO$ in QCD

The renormalization constant $Z_J$ of the flavor-singlet axial-vector current with a non-anticommuting $\gamma_5$ in dimensional regularization is determined to order $\alpha_s^3$ in QCD with massless quarks. The result is obtained by computing the matrix elements of the operators appearing in the axial-anomaly equation between the vacuum and a state of two (off-shell) gluons to 4-loop order. Furthermore, through this computation, the equality between the $\overline{\mathrm{MS}}$ renormalization constant $Z_{F\tilde{F}}$ associated with the operator $\big[F \tilde{F} \big]_{R}$ and that of $\alpha_s$ is verified explicitly to hold true at 4-loop order.

Speaker: Long Chen (Max Planck Institute for Physics)

Chen_Talk.pdf

591 A pitfall in applying a non-anticommuting gamma5 in qqbar to > Z+Higgs amplitudes

We show how the polarized amplitudes of $b \bar{b} \rightarrow Z h$ associated with a non-vanishing $b$-quark Yukawa coupling and a scalar or pseudoscalar Higgs boson $h$ can be built up solely from vector form factors (FF) of properly grouped classes of diagrams, bypassing completely the need of explicitly manipulating $\gamma_5$ in dimensional regularization.

In addition, the FFs of a class of corrections to $q \bar{q} \rightarrow ZH$ proportional to the top-Yukawa coupling are obtained analytically to two-loop order in QCD in the heavy-top limit. We address a pitfall that occurs when applying the non-anticommutating $\gamma_5$ prescription to this class of contributions that has been overlooked so far in the literature.

Speaker: Taushif Ahmed (Max-Planck-Institut für Physik)

eps-hep2021_taushif.pdf

592 The Electroweak Hamiltonian in the Gradient Flow Formalism

Over the last decade, the gradient flow formalism became an important tool for lattice simulations of Quantum Chromodynamics. Most prominently, scale setting strategies based on the gradient flow superseded previous strategies. Moreover, the gradient flow offers remarkable renormalization properties which pave the way for cross-fertilization between perturbative and lattice calculations.
In this talk we introduce the gradient flow formalism and outline the perturbative approach. Employing the flowed operator product expansion, we construct the flowed equivalents of the current-current operators of the electroweak Hamiltonian. They allow for simpler transformations between lattice and perturbative schemes and might reduce the uncertainties of theoretical predictions for low-energy flavor observables.

Speaker: Mr Fabian Lange (KIT & RWTH Aachen University)

EPS-HEP-Lange.pdf

593 Subleading colour effects and spin correlations in the PanScales showers

In the context of the PanScales parton shower project I will describe two advances in the development of final-state parton showers with controlled logarithmic accuracy. The first (arXiv:2011.10054) involves simple new algorithms to resolve the long-standing issue of incorrect subleading-colour contributions at leading logarithmic (LL) accuracy in dipole- and antenna-type showers, and also enables the PanScales showers to obtain full-colour NLL accuracy for many observables. The second (arXiv:2103.16526) concerns spin correlations, where we propose a spinor-product based implementation of the well-established Collins algorithm. We verify the logarithmic accuracy of the results with separate purely collinear calculations, using novel spin-sensitive jet observables that are of potential interest also for future experimental measurements.

Speaker: Ludovic Scyboz (University of Oxford)

EPS21_Scyboz_ColourSpin.pdf

594 Comparison of public codes for Drell-Yan processes at NNLO accuracy

We present a detailed comparison of predictions computed by four publicly available computer codes for Drell-Yan processes at the LHC and Tevatron colliders. We point out that while there is agreement among the predictions at the next-to-leading order accuracy, the predictions at the next-to-next-to-leading order (NNLO) differ, whose extent depends on the observable. The sizes of the differences in general are at least similar, sometimes larger than the sizes of the NNLO corrections themselves. The talk will be based on arXiv: 2104.02400.

Speaker: Zoltan Trocsanyi (ELTE Eotvos Lorand University)

Trocsanyi-PrecisionDY.pdf

595 All-plus helicity off-shell gauge invariant multigluon amplitudes at one loop

We calculate one loop scattering amplitudes for arbitrary number of positive helicity on-shell gluons and one off-shell gluon treated within the quasi-multi Regge kinematics. The result is fully gauge invariant and possesses the correct on-shell limit. Our method is based on embedding the off-shell process, together with contributions needed to retain gauge invariance, in a bigger fully on-shell process with auxiliary quark or gluon line.

Speaker: Etienne Blanco (IFJ-PAN)

HEP-EPS_2021_Off-shell_gluons_amplitudes_presentation.pdf

596 All loop causal representation of scattering amplitudes

The loop-tree duality (LTD) has become a novelty
alternative to bootstrap the numerical evaluation of
multi-loop scattering amplitudes.
It has indeed been found that Feynman integrands,
after the application of LTD, displays a representation
containing only physical information, the so-called
causal representation.
In this talk, I discuss the all causal representation
of multi-loop Feynman integrands, recently found in terms
of features that describe a loop topology, cusps,
and edges.
Likewise, in order to elucidate the numerical stability
in the LTD integrands, we present applications that
involve the numerical evaluation of four-loop integrals
with the presence of several kinematic invariants.

Speaker: William J. Torres Bobadilla (Max-Planck-Institute for Physics)

TorresBobadilla.pdf

T07: Top and Electroweak Physics: Part 6

20 Minutes talks are meant as 15'+5'
15 Minutes talks are meant as 12'+3'

Conveners: Alexander Grohsjean (CMS (CMS Fachgruppe TOP)), Eleni Vryonidou

597 Measurement of top-quark electroweak couplings in associated top quark production with vector bosons with ATLAS and CMS detector

A comprehensive set of inclusive and differential measurements of top quark pair production in association with EWK bosons (W, Z or ɣ) , including searches for rare single top production processes (tZq) is presented.

Speaker: David Walter (CMS (CMS Fachgruppe TOP))

210730_EPSHEP_dwalter_v6.pdf

598 Evidence for four-top-quarks production with the ATLAS detector at the Large Hadron Collider

Results are presented of searches in ATLAS for four-top-quark production. This rare process, with a predicted cross section of 12 fb in the Standard Model, has not been observed yet by experiment. The analysis is based on data from proton--proton collisions at a centre-of-mass energy of 13 TeV collected with the ATLAS detector during run 2 of the CERN Large Hadron Collider, and corresponding to an integrated luminosity of 139 inverse fb. The search is performed in several final states, either with multiple or same-sign leptons or with one or two leptons and a large jet and b-jet multiplicity. Background models are carefully constructed and validated, for top quark pair production with additional gauge bosons and (b-)jets and other background processes. The signal strength is extracted with a fit to distributions of several sensitive observables. The combination of the searches yields 4.7 sigma evidence for four-top-quark production.

Speaker: Paolo Sabatini (Instituto de Fisica Corpuscular (IFIC), Centro Mixto Universidad de Valencia - CSIC)

EPS21-ATLAStttt__v3.pdf

599 Probing EFT in canonical and associated top quark productions in CMS

Top quark production can probe physics beyond the SM in different ways. The Effective Field Theory (EFT) framework allows searching for BSM effects in a model independent way. CMS experiment is pioneering EFT measurements that move towards using full potential of the data in the most global way possible. This talk covers various analysis strategies pursued in CMS for constraining top quark EFT couplings with the focus on the latest results.

Speaker: Robert Schöfbeck

21-07-30 Probing EFT in canonical and associated top quark productions in CMS.pdf

600 Top quark physics at ILC

The top quark has not yet been studied in the extremely favorable and low background environment of e+e- annihilation. This talk will review the opportunities for precision measurements of the top quark properties at the International Linear Collider (ILC). These include the archival measurement of the top quark mass, the search for beyond-Standard Model contributions to the top quark electroweak form factors, and the search for CP violation in the top quark couplings.

Speaker: Roman Poeschl (not set)

eps-2021.pdf

601 Top physics at the LHeC and the FCC-he

The LHeC and the FCC-he offer unique prospects for the measurement of top properties in energy frontier, luminous $ep$ scattering. An update of the 2012 Conceptual Design Report was produced last year [1]. In this talk we will revisit the determination of the top mass through inclusive measurements. In addition, we will address the possibilities for precise measurements of $Wtq$ and $\gamma tq$ couplings, and competitive searches for FCNC top couplings.

[1] LHeC Collaboration and FCC-he Study Group, P. Agostini et al., e-Print: 2007.14491 [hep-ex], to appear in J. Phys. G.

Speaker: Dr SUBHASISH BEHERA (Johannes Gutenberg University Mainz, Germany)

SB_TopFCNC_EPS_final.pdf

602 The top quark electro-weak couplings after LHC Run 2

As the heaviest particle of the model, with a mass close to the electroweak scale, the top quark is an interesting candidate to look for hints of new physics. The electroweak couplings of the top quarks are specially relevant in many extensions of the Standard Model. Indeed, as the top quark was not produced in the previous generation of electron-positron colliders most of its electro-weak couplings can only be constrained with the data from the Large Hadron Collider. In order to analyze if there is still room for new physics in the electro-weak couplings of the top quark, we perform a global fit to these couplings. Following the Standard Model Effective Field Theory formalism we have constrained the Wilson coefficients of the dimension-six operators that affect the top quark electro-weak couplings. In this work we consider, for the first time, the QCD corrections at NLO for most of the processes included. Furthermore, we have included recently measured processes, such as $tZq$ and $t\gamma$$q$, and the first differential measurements in $t\bar{t}Z$ and $t\bar{t}\gamma$ production. A special effort is made to understand the uncertainties due to the truncation of the EFT expansion and due to the poorly known correlations among measurements. As the main result, we present a robust set of bounds on the relevant operator coefficients, which represents a significant improvement with respect to previous results.
The results and paper are being finalized and we plan to upload the pre-print in May 2021.

Speaker: Víctor Miralles (IFIC (CSIC-UV))

EPS-HEP.pdf

T08: Flavour Physics and CP Violation: Part 8

Conveners: Francesco Dettori (Università degli Studi di Cagliari), Nuno Leonardo (LIP & IST)

603 Lepton flavour universality tests at LHCb

The coupling of the electroweak gauge bosons of the Standard Model (SM) to leptons is independent of the lepton flavour. Extensions of the SM do not necessarily respect this lepton flavour universality. Semileptonic rare decays of heavy flavour, to which new particles can give sizeable contributions, allow for sensitive tests of lepton flavour universality, and constitute powerful indirect searches for phenomena beyond the SM. Of particular interest are rare b->sll decays that are readily accessible at the LHCb experiment. Recent results from LHCb on lepton flavour universality in rare b->sll decays are discussed.

Speaker: Michael McCann (Imperial College (GB))

20210730_LFU_tests_with_LHCb.pdf

604 Addressing the muon anomalies with muon-flavored leptoquarks

Significant deviations from SM predictions have been observed in $ b \to s \mu^+ \mu^-$ decays and in the muon (g-2). Scalar leptoquark extensions of the SM are known to be able to address these anomalies, but generically give rise to lepton flavor violation (LFV) or even proton decay. We propose new muon flavored gauge symmetries as a guiding principle for leptoquark models that preserve the global symmetries of SM and explain the non-observation of LFV. A minimal model is shown to easily accommodate the anomalies without encountering other experimental constraints. This talk is mainly based on arXiv:2103.13991.

Speaker: Dr Anders Eller Thomsen (University of Bern)

2021_EPS-HEP.pdf

605 Electroweak penguin decays at LHCb

Rare b->sll decays are flavour-changing neutral-current processes that are forbidden at the lowest perturbative order in the Standard Model (SM). As a consequence, new particles in SM extensions can significantly affect the branching fractions of these decays and their angular distributions. The LHCb experiment is ideally suited for the analysis of these decays due to its high trigger efficiency, as well as excellent tracking and particle identification performance. Recent results from the LHCb experiment in the area of b->sll decays are presented and their interpretation is discussed.

Speaker: Christoph Langenbruch (RWTH Aachen)

langenbruch.pdf

606 Probing B-anomalies via dimuon tails at the FCC

Recent measurements of lepton-universality ratios and $B_s\to\mu^+ \mu^-$ decay point to possible new physics contribution to $b\to s \mu^+ \mu^-$ transitions. If new physics really is present, then it is possible that it could lie at a scale beyond the kinematical reach of the LHC or even that of a future, more energetic, proton-proton collider. In this instance, the relevant new physics is encapsulated by effective semi-leptonic four-fermion operators and its effects could be indirectly detected in the tails of dilepton invariant mass distributions.

In this talk, I will discuss the sensitivity of a future proton-proton collider to the relevant four-fermion operators when considering an inclusive dimuon final state at a centre of mass energies of 100 TeV. I will present 95% C.L. exclusion bounds on the Wilson coefficients of these operators as well as the values needed for a 5$\sigma$ rejection of the SM background. Throughout this, I shall also discuss the validity of theses bounds within our EFT approach along with the effect that both NLO QCD and EW corrections to our EFT signal have on the sensitivity.

Speaker: Bradley Garland (University of Sussex)

EPS_HEP2021 Talk.pdf

607 Interplay between dineutrino modes with semileptonic decays

$SU(2)_L$-invariance links charged dilepton $\bar{q}\,q^\prime\,\bar{\ell}\,\ell$ and dineutrino $\bar{q}\,q^\prime\,\bar{\nu}\,\nu$ couplings. This connection can be established using SMEFT and holds if only SM-like left-handed light neutrinos are present. It allows to perform complementary experimental tests of lepton universality and charged lepton flavor conservation with flavor-summed dineutrino observables. The phenomenological implications are discussed in detail for the branching ratios of rare charm decays $c \to u\,\nu\bar\nu$, such as $D^+\to\pi^+\,\nu\bar\nu$, and rare $B$ decays $b \to q \,\nu \bar \nu$ with $q=d,s$ decays.

Speaker: Hector Gisbert Mullor (TU Dortmund)

EPS_HEP_HGisbert.pdf

608 Implications of LHCb Data for Lepton Flavour Universality Violation

Recently, LHCb has confirmed the evidence for lepton flavour universality violation in the $R_K$ ratio with 3.1$\sigma$ significance. We present new physics implications within a model-independent approach and make projections for future measurements that indicate that LHCb will be in the position to discover lepton non-universality with the Run 3 data in a single observable. We also present other ratios which are able to differentiate between various new physics scenarios in the near future. Moreover, we present global fits of rare $B$-decays within multidimensional fits involving up to all the relevant 20 Wilson coefficients and compare different scenarios via likelihood ratio tests, applying Wilks’ theorem.

Speaker: Siavash Neshatpour (Lyon University)

Neshatpour_EPS2021.pdf

609 Searches for rare decays at CMS

Rare decays provide a sensitive laboratory to search for New Physics. Recent CMS results concerning rare decays are presented.

Speaker: Bhargav Joshi (University of Florida)

EPS_30_07_2021.pdf

610 Very rare decays at LHCb

Decays of b-hadrons that are very suppressed in the Standard Model, such as fully leptonic flavour-changing neutral-current transitions or lepton flavour violating decays, are particularly clean probes for New Physics. The LHCb experiment is designed for the study of b-hadron decays and ideally suited for the analysis of very rare decays due to its high trigger efficiency, as well as excellent tracking and particle identification performance. Recent results from the LHCb experiment on very rare decays are presented.

Speaker: Miguel Ramos Pernas (University of Warwick (GB))

Miguel_Ramos_Pernas-Very_rare_decays_at_LHCb.pdf

T10: Searches for New Physics: Part 9

All talks in this session will be 12 mins + 3 mins for the discussion.

Convener: Akitaka Ariga (Chiba University)

611 Prospects for long-lived particle searches at Belle II

The Belle II experiment at the asymmetric $e^+e^-$ collider, SuperKEKB, is a substantial upgrade of the Belle/KEKB experiment. Belle II aims to record 50 ab$^{-1}$ of data over the course of the project. During the first physics runs in 2018-2020, around 100 fb$^{-1}$ were collected. Large improvements in the instantaneous luminosity are expected in the coming years. The Belle II detector benefits from a larger tracking detector and improved tracking and vertexing algorithms with respect to Belle, allowing for improvements in the reconstruction of vertices that are displaced from the interaction point. This talk will review the prospects for long-lived particle searches at Belle II. The experiment can be used to search for long lived particles produced directly in the interaction, or in meson and lepton decays.

Tau

Speaker: Torben Ferber (BELLE (BELLE II Experiment))

ferber_2021_07_26_EPS_v1.pdf

612 New physics searches with the ILD detector at the ILC

Although the LHC experiments have searched for and excluded many proposed new particles up to masses close to 1 TeV, there are many scenarios that are difficult to address at a hadron collider.  This talk will review a number of these scenarios and present the expectations for searches at an electron-positron collider such as the International Linear Collider.   The cases discussed include the light Higgsino, the stau lepton in the coannihilation region relevant to dark matter, and heavy vector bosons coupling to the s-channel in e+e- annihilation. The studies are based on the ILD concept at the ILC.

Speaker: Carl Mikael Berggren (FTX (FTX Fachgruppe SLB))

berggren-epshep-zoom-jul21.pdf

613 The CLIC potential for new physics

The Compact Linear Collider (CLIC) is a mature option for a future
electron-positron collider operating at centre-of-mass energies of up
to 3 TeV. CLIC would be built and operated in a staged approach with
three centre-of-mass energy stages currently assumed to be 380 GeV,
1.5 TeV, and 3 TeV. A selection of results from recent studies will be
presented showing that CLIC has excellent sensitivity to many BSM
physics scenarios. New particles can be discovered in a
model-independent way almost up to the kinematic limit. Compared with
hadron colliders, the low background conditions at CLIC provide
extended discovery potential, in particular for the production through
electroweak and/or Higgs boson interactions. This includes scenarios
with extended scalar sectors, also motivated by dark matter, which can
be searched for using associated production processes or cascade
decays involving electroweak gauge bosons.

Speaker: Jan Klamka (University of Warsaw)

clic_potential_eps-hep.pdf

614 The IDM and THDMa - current constraints and future prospects

The THDMa is a new physics model that extends the scalar sector of the Standard Model by an additional doublet as well as a pseudoscalar singlet and allows for mixing between all possible scalar states. In the gauge eigenbasis, the additional pseudoscalar serves as a portal to the dark sector, with a priori any dark matter spin states. The Inert Doublet model is another intriguing new physics model containing a dark matter candidate, which so far has not been investigated by the LHC experiments. I discuss current bounds as well as discovery prospects for both models at current and future colliders.

Speaker: Tania Robens (Rudjer Boskovic Institute (HR))

robens_eps21.pdf

615 An unambiguous test of positivity at lepton colliders

The diphoton channel at lepton colliders, $e^+e^- (\mu^+\mu^-) \to \gamma \gamma$, has a remarkable feature that the leading new physics contribution comes only from dimension-eight operators. This contribution is subject to a set of positivity bounds, derived from fundamental principles of Quantum Field Theory, such as unitarity, locality and analyticity. These positivity bounds are thus applicable to the most direct observable -- the diphoton cross sections. This unique feature provides a clear, robust, and unambiguous test of these principles. We estimate the capability of various future lepton colliders in probing the dimension-eight operators and testing the positivity bounds in this channel. We show that positivity bounds can lift certain degeneracies among the effective operators and significantly change the perspectives of a global analysis. We also perform a combined analysis of the $\gamma\gamma/Z\gamma/ZZ$ processes in the high energy limit and point out the important interplay among them.

based on 2011.03055

Speaker: Jiayin Gu

Jiayin_Gu_pos_EPS21.pdf

616 (New) Physics at a multi-TeV Muon Collider

We discuss the physics potential of a multi-TeV muon collider. We present the results for the main SM processes together with popular BSM models, emphasizing the annihilation and VBF regime at very-high energies. We also discuss some preliminary results about the Effective Vector Boson Approximation and its implementation in MadGraph5_aMC@NLO.

Speaker: Antonio Costantini

epshep_2021_Costantini.pdf

617 Probing muon philic forces at a muon collider

Experimental anomalies like the muon g-2 and the decay of the B meson $B\to K\mu\mu$ suggest the existence of interactions that predominantly talk to the muon. The muon philic nature of these hypothetical interactions is necessary to avoid experimental constraints on lepton flavor violating processes. Models that explain g-2 feature either light weakly coupled states or heavy strongly coupled new particles. Most explanations for $B\to K\mu\mu$ feature only the latter option. In both cases, we show how a combination of direct and indirect signatures at a muon collider can cover the entire parameter space that explains the aforementioned anomalies in the context of a set of benchmark models.

Speaker: Rodolfo Capdevilla (Perimeter Institute and University of Toronto)

618 Probing new physics at the LUXE experiment

The proposed LUXE experiment at the DESY aims to probe QED at the nonperturbative regime in collisions between high-intensity laser pulses and high-energy electron or photon beams. This setup also provides a unique opportunity to search for physics beyond the standard model. In this talk we show that by leveraging the large photon flux generated at LUXE, one can probe axion-like-particles (ALPs) up to a mass of 350 MeV and with photon coupling of 3x10^-6 GeV^-1. This reach is comparable to FASER2 and NA62. In addition, we will discuss other probes of new physics such as the ALP-electron coupling.

Speaker: Noam Tal Hod (Weizmann Institute of Science)

Noam_EPS2021_BSM_at_LUXE_30072021.pdf

T12: Detector R&D and Data Handling: Calorimeter

Conveners: Alessandro Cardini (INFN Sezione di Cagliari, Italy), Annika Vauth (Universität Hamburg)

619 Status and plans for the CMS High Granularity Calorimeter upgrade project

The CMS Collaboration is preparing to build replacement endcap calorimeters for the HL-LHC era. The new high-granularity calorimeter (HGCAL) is, as the name implies, a highly-granular sampling calorimeter with approximately six million silicon sensor channels (~1.1 cm^2 or 0.5 cm^2 cells) and about four hundred thousand channels of scintillator tiles readout with on-tile silicon photomultipliers. The calorimeter is designed to operate in the harsh radiation environment at the HL-LHC, where the average number of interactions per bunch crossing is expected to exceed 140. Besides measuring energy and position of the energy deposits the electronics is also designed to measure the time of their arrival with a precision on the order of 50 ps. In this talk, the reasoning and ideas behind the HGCAL, the current status of the project, the many lessons learnt so far, in particular from beam tests, and the challenges ahead will be presented.

Speaker: Clemens Lange (CERN)

LangeClemens_20210730_EPSHEP_HGCALStatusAndPlans.pdf

620 Design and construction status of the Mu2e crystal calorimeter

The Mu2e experiment at Fermi National Accelerator Laboratory searches for the charged-lepton flavor violating neutrino-less conversion of a negative muon into an electron in the field of an aluminum nucleus. The dynamics of such a process is well modelled by a two-body decay, resulting in a mono-energetic electron with energy slightly below the muon rest mass (104.967 MeV). Mu2e will reach a single event sensitivity of about 3x10−17 that corresponds to four orders of magnitude improvement with respect to the current best limit.
The calorimeter requirements are to achieve an energy resolution better than 10% and a timiong resolution better than 500 ps at 100 MeV in order to provide the needed $\mu$/e particle identification, an online trigger filter while aiding the track reconstruction capabilities. It consists of two disks of un-doped CsI crystals, each one read out by two large area UV-extended SiPMs.
In this talk, the status of construction and QC performed on the produced crystals and photosensors, the development of the rad-hard electronics and the most important results of the irradiation tests done on the different components are summarized. The production of electronics is underway and we will summarize the QC test performed on the analog electronics and on the integrated SIPM+FEE units. Construction of the mechanical parts is also progressing well. Status and plans for the final assembly are also described. We expect to start assembly of the disk in summer 2021 assuming that the pandemics status will allow the INFN team to be present at Fermilab.
In the meanwhile, a complete vertical slice test with the final electronics is in progress on the large calorimeter prototype, dubbed Module-0, at the Frascati Cosmic Rays test stand. First calibration and performance results will be shown.

Speaker: Eleonora Diociaiuti

DiociaiutiEPS_online.pdf

621 Implementation of large imaging calorimeters

The next generation of collider detectors will make full use of Particle Flow algorithms, requiring high precision tracking and full imaging calorimeters. The latter, thanks to granularity improvements by 2 to 3 orders of magnitude compared to existing devices, have been developed during the past 15 years by the CALICE collaboration and are now reaching maturity. The state-of-the-art status and the remaining challenges will be presented for all investigated readout types: silicon diode and scintillator for a electromagnetic calorimeter, gaseous with semi-digital readout as well as scintillator with SiPM readout for a hadronic one. We will describe the commissioning, including beam test results, of large scale technological prototypes and the raw performances such as energy resolution, linearity and studies exploiting the distinct features of granular calorimeters regarding pattern recognition. Beyond these prototypes, the design of experiments addressing the requirements and potential of imaging calorimetry will be discussed. In addition, less established but promising techniques for dedicated devices inverse APD or segmented crystal calorimeters will also be highlighted. In the last year also first results with high resolution timing devices have been obtained. The integration of these devices in the CALICE prototypes is one of the major goals in the coming years.

Speaker: Adrian Irles (IFIC - CSIC/UV)

20210730_v0.pdf

622 Performance of a highly compact electromagnetic calorimeter for future electron-positron colliders

The FCAL Collaboration is presently designing and testing electromagnetic sampling calorimeters foreseen for the forward region of future detectors at electron-positron colliders. Two calorimeters, LumiCal and BeamCal, are foreseen for a precise and instant measurement of the luminosity, respectively. For the integrated luminosity, obtained from the rate of low angle Bhabha scattering events, a precision of better than 10^−3 is required from the physics program. The precise measurement of electromagnetic showers on top of background favours highly compact calorimeter designs. BeamCal sensors have to withstand high radiation doses.
The performance of a LumiCal silicon-tungsten prototype was studied in several test-beam campaigns at DESY using electrons with energies between 1 and 5 GeV. The results demonstrate an effective Moliere radius of about 8mm, a shower position resolution of 0.44mm and excellent linearity of the response. The results are in a good agreement with the MC simulation.
Recently, a dedicated multi-channel ultra-low power ASIC for the LumiCal readout was used in test-beam studies for the first time. Preliminary results will be presented. In addition, an ASIC with a dual readout scheme for the BeamCal is being developed.
Also, results on radiation hardness studies of different sensor candidates will be reported.

Speaker: Dr Szymon Bugiel (Institut Pluridisciplinaire Hubert CURIEN (IPHC))

2021_07_EPS_Lumical.pdf

623 Combining Dual-Readout Crystals and Fibers in a Hybrid Calorimeter for the IDEA Experiment

Crystal calorimetry has a long history of pushing the frontier of high energy resolution measurements for EM particles. Recent technological developments in the fields of crystal manufacturing and photodetector developments (SiPMs) have opened new perspectives on how a segmented crystal calorimeter with dual-readout capabilities could be exploited for particle detectors at future collider experiments. In this contribution, we will discuss how a EM crystal calorimeter can be cost-effectively integrated with the fiber-based calorimeter of the IDEA detector to achieve an energy resolution of $3\%/\sqrt{E}$ for EM particles and $27\%/\sqrt{E}$ for neutral hadrons. We will also show how the extension of the dual-readout method in such a longitudinally segmented hybrid calorimeter can achieve an energy resolution close to 5\% for 50 GeV jets and discuss the potential of such calorimeter in the context of future particle flow algorithms.

Speaker: Marco Toliman Lucchini (Università & INFN, Milano-Bicocca (IT))

EPS-HEP-2021_Combining Dual-Readout Crystals and Fibers in a Hybrid Calorimeter for the IDEA Experiment.pdf

624 RADiCAL - Ultracompact Radiation-hard Fast-timing EM Calorimetry

To address the challenges of providing high performance EM calorimetry in future experiments under high luminosity and difficult radiation and pileup conditions, R&D is being conducted on promising optical-based technologies that can inform the design of future detectors, with emphasis on ultra-compactness, excellent energy resolution and spatial resolution, and especially fast timing capability.

The strategy builds upon the following concepts: use of dense materials to minimize the cross sections and lengths (depths) of detector elements; maintaining Molière Radii of the structures as small as possible; use of optical techniques that can provide high efficiency and fast response while keeping optical paths as short as possible; and use of radiation resistant, high efficiency photosensors.

High material density is achieved by using thin layers of tungsten absorber interleaved with active layers of dense, highly efficient crystal or ceramic scintillator. Scintillator approaches under investigation include rare-earth 3+ activated materials Ce3+ and Pr3+ for brightness and Ca co-doping for improved (faster) fluorescence decay time.

Light collection and transfer from the scintillation layers to photosensors is enabled by the development and refinement of new waveshifters (WLS) and their incorporation into radiation hard quartz waveguide elements. WLS developments include the fast organic dyes of the DSB1 type, ESIPT (excited state intermolecular proton transfer) dyes having very low optical self-absorption, and inorganic materials such as LuAG:Ce, having high radiation resistance.

Optical waveguide approaches include thick-wall quartz capillaries containing WLS cores for: (1) energy measurement; (2) with WLS materials strategically placed at the location of the EM shower maximum to provide timing of EM showers, and (3) with WLS shifter elements placed at various depth locations to provide depth segmentation and angular measurement of EM shower development.

Light from the wave shifters is detected by pixelated, Geiger-mode photosensors.
These include small pixel (5-7 micron) silicon photomultiplier devices (SiPM) operated at low gain and cooled (typically -35°C or below), and potentially via large band-gap devices such as GaInP.

Underway or in planning are bench, beam and radiation tests of individual components and modular elements. Recent results and program plans will be presented.

Speaker: Randy Ruchti (University of Notre Dame)

RADiCAL-Ultracompact Radiation-hard Fast-timing EM Calorimetry.pdf

625 GAGG scintillation crystals family for HEP instrumentation

Homogeneous electromagnetic calorimeters made of crystalline scintillation elements played a crucial role in the discoveries in high-energy physics experiments at colliders during the last three decades [1]. Nevertheless, their future application at high luminosity collider facilities (High Luminosity LHC, FCC in hh mode) might become limited by radiation damage effects under the charged and neutral hadrons in the bulk elements. The high luminosity puts in the list of the priorities the combination of the capability for the high time resolution and radiation tolerance as the primary properties of the scintillation material to be exploited. Recently it was demonstrated that compositionally disordered crystalline materials of gallium-aluminum garnets meet these requirements [2]. Their composition may be engineered from ternary to quaternary garnets allowing tuning of the properties of the material for a particular application.
The combination of the scintillation properties, particularly the high light yield up to 50000 photons/MeV, the decay time shorter than 80 ns and a high time resolution better than 160 ps with a modern SiPM photosensor, and outstanding radiation hardness and chemical and mechanical stability make the complex garnet oxides the candidates of choice for a range of various applications in HEP experiments.
In our report we review the last achievements for the properties of multidoped Gd3Al2Ga3O12 - (Gdx-Y1-x)Al2Ga3O12 crystal family produced by the wide-spread Czochralski crystal growth technique. Superior mechanical properties make possible production of different shape scintillation elements to equip heterogeneous detecting units of “Shaslyk” or SPACAL type. Due to its cubic crystalline structure, the crystals of the family may be obtained as a polycrystalline ceramic using various techniques, including 3D printing [3]; this further widens the range of the possible applications.
1. P Lecoq, A Gektin, M Korzhik, Inorganic Scintillators for Detector Systems, Springer, 2016, p.408
2. M Korzhik, G.Tamulaitis, A.Vasil’ev, Physics of the fast phenomena in scintillators. Springer, 2020, p.350
3. G.A. Dosovitskiy et. al, CrystEngComm 19 (2017), 4260-4264

Speaker: Prof. Mikhail Korzhik (NRC “Kurchatov Institute”-IREA, Moscow, Russia - Institute for Nuclear Problems, Minsk, Belarus)

Korzhik-30-07-21-final.pdf

626 Enhanced electromagnetic processes in oriented crystals for applications in high-performance calorimetry

Nowadays, it is well known that the electromagnetic interaction between high-energy particles and matter experiences substantial modifications when the latter consists of a crystalline medium and its lattice axes are almost parallel to the input beam direction. In particular, strong boosts to both the Bremsstrahlung (by electrons and positrons) and the pair production (by photons) cross sections in high-density oriented crystals have been observed in the 10-to-100 GeV regime. This effect proves particularly appealing when it comes to inorganic scintillators, given the possibility to exploit it for the development of high-performance, ultra-compact electromagnetic calorimeters — some applications to future high-energy physics experiments already being under study, e.g. the KLEVER Small Angle Calorimeter. This work provides a detailed discussion of the results obtained by probing a PWO (lead tungstate) oriented sample with 120 GeV/$c$ electrons and positrons at the CERN North Area: in particular, direct measurements of the enhancement in the scintillation light production with respect to the random lattice orientation are presented, and a comparison between the outcomes obtained with electrons and positrons is made. Moreover, output radiation measurements on oriented samples of other commonly used inorganic scintillator such as BGO and YAG have been recently performed in the sub-GeV regime at the MAMI-B facility: an overview on the resulting characterisation is given.

Speaker: Mattia Soldani (Università degli Studi di Ferrara & INFN Ferrara)

21_07_30_epshep2021_soldani.pdf

T13 - Accelerator for HEP: Part 4

627 The Development of Energy Recovery Linacs

A summary will be given of the current status and the prospects for energy recovery linac (ERL) technology and its possible application for future ep and e+e- colliders, as well as for low energy particle and nuclear physics. The talk will give an overview of ERL development facilities, current and future, describe key technology challenges and also cover the aspect of sustainability of ERLs. Energy recovery has been recognised as one of the major new, promising accelerator technologies of the future by the recent deliberation on the strategy for particle physics. The presentation is on behalf of an 18 person expert panel on ERL which develops a roadmap on ERL technology developments towards the end of 21, following a mandate by CERN Council and the group of directors of larger laboratories (LDG) associated to CERN.

Speaker: Max Klein (H1/LIVE (H1 / Liverpool))

ERLmkEPSf.pdf

628 Muon Collider

The muon collider offers a unique opportunity to reach high-energy lepton
collisions with high luminosity. Following the Update of the European Strategy
for Particle Physics CERN is hosting a new, forming muon collider collaboration.
The muon collider is also considered in the Roadmap for Accelerator R&D, which
is being developed.
The presentation gives a short introduction into the concept and highlights
the challenges that have to be addressed together with the plan of the
collaboration.

Speaker: Daniel Schulte (CERN)

629 Plasma-Based and Laser Accelerators for High-Energy Physics

Experiments demonstrated that plasma-based accelerators can produce high energy electrons (e.g., 8 and 42GeV) in short distances (20 and 85cm, respectively). They are very high gradient accelerators (i.e., 50GeV/m) and therefore hold the promise to be more compact and affordable than RF-based linear accelerators. An alternative path investigates the use of dielectric accelerators with high accelerating fields. The challenge for these new accelerators driven by a laser pulse or a relativistic particle bunch is to produce beams with parameters that would make them competitive in terms of luminosity and efficiency. In follow-up to the European strategy of particle physics, an Expert Panel for High Gradient Plasma and Laser accelerators has recently been set up. We present specificities of these accelerators, and discuss various inputs received on how to meet the challenges posed by various HEP applications.

Speaker: Ralph Assmann (MPY1 (MPY Fachgruppe 1))

2021-07-30-eps-hep-plasma-assmann-out-public.pdf

2021-07-30-eps-hep-plasma-assmann-out-public.pptx

630 Status and Perspectives of High-Field Magnets R&D for Particle Physics

The CERN Council has endorsed in June 2020 the Update of the European Strategy for Particle Physics. The strategy document contains a strong recommendation to reinforce R&D on key technologies for future accelerators, and in particular high field magnets, including HTS.
To follow up on the implementation of this recommendation, a High Field Magnet Expert Panel (HFM-EP) has been convened under the auspices of the European Large National Laboratories Directors Group (LDG) to create a prioritized R&D roadmap for the High Field Magnets.
The proceedings of the HFM-EP, planned to be endorsed by the CERN council in December 2021, will document this roadmap. They will include the current state-of-the-art and the scientific drivers for High Field Magnets R&D, the progress needed to enable this technology for future facilities, the potential deliverables and demonstrators for the next decade, a prioritized work plan, considering the capabilities and interests of stakeholders, and a range of scenarios for engagement.
We will describe here the status of this work including a technology review about the state-of-the-art, R&D plans, challenges and future opportunities for High Field Magnets for future accelerators.

Speaker: Pierre Vedrine

EPS-HEP HFM Status 30 July 2021.pptx

631 Development and use of high gradient RF technology for compact linacs

The high-gradient linac technology developed by the CLIC study is now being adopted by a wide range of accelerator applications. These range from electron linac applications such as X-ray free electron lasers (XFELs), Inverse Compton Scattering (ICS) sources, beam manipulating components like energy spread linearizers and transverse deflectors through to medical accelerators as well as proton applications like high-gradient low-beta accelerating cavities and large acceptance radio frequency quadrupoles (RFQs). Examples of these applications are presented. The adoption is an important example of technology transfer and is providing a greatly expanded community developing high-gradient technology further.

Speaker: Dr Walter Wuensch (CERN)

applications of X and HG 2021-7-30.pptx

T14: Outreach, Education and Diversity: Part 5

632 Towards an inclusive society by making Astronomy accessible to the blind

At Guezet the sky is perfectly dark. That’s the type of sky the astronomers like to work with at night. Therefore, such conditions are better at Guzet than at the Pic du Midi where observers have to climb steep montains. Every summer, on the Col d'Escot, at an altitude of 1700 meters and from Chalet Beauregard, Astronomers are used to coming there to take advantage of this exceptional place for observation.

This incredible project was born in 2016, Jacques Croiziers, President of the association, followed by six members, have realized that Astronomy should be accessible to all. Indeed, the sky does not belong to a certain category of people. Their primary motivation was to offer an observatory accessible to all people with disabilities and especially the visually impaired people. It is important to show that Science can be accessible. However, the cost is impressive 700 000 euros and requires the contributions of partners including local and national institutions and organisations for the development of the economical region, scientific laboratories with Researchers from different topics. In short, the project supported by Ciel d'Occitanie will allow to join our efforts. The relevant materials suitable for disable people will be identified. In addition, new methods and materials will be developed by the large collaborations allowed by this project. Thank to this observatory, a french group will be able to interact with international projects on the accessibility of Astronomy.

Speaker: Ludovic Petitdemange

talk.pdf

633 The REINFORCE citizen-science project and the search for new long-lived particles at the LHC.

The REINFORCE EU project (link) engages and supports citizens to cooperate with researchers and actively contribute to the development of new knowledge for the needs of science and society. After a brief description of the four demonstrators comprising REINFORCE, we will present in detail the demonstrator titled “Search for new particles at the LHC”, which will engage citizen-scientists in searches for new elementary particles produced in the high-energy proton-proton collisions at the LHC of CERN.

Speaker: Stylianos Angelidakis (National and Kapodistrian University of Athens (GR))

REINFORCE_HEP2021.pdf

634 Outreach at LHCb: Through the online boom and beyond

Over the past 16 months, the landscape of science communication has radically changed to adapt to a situation of limited mobility and exploding internet usage. Following this trend, the LHCb collaboration has increased its online presence through a wide communication around its latest results, and has built experience in organising virtual visits of the experiment, while pursuing its efforts to strengthen its previous outreach activities. This talk will give an overview of the coverage of recent LHCb results in social and internet-based media through the examples of hadron spectroscopy and the cautious excitement around lepton-flavour universality tests. Different setups for virtual tours of the detector will also be discussed, and updates of the LHCb Masterclass aimed at improving the students experience will be shown. In parallel with this, the collaboration is preparing for the future, and the design of the new LHCb exhibition to be installed on the detector site will be presented.

Speaker: Violaine Bellée

2021_07_30_LHCPOutreach_BelleeSMALLER.pdf

635 Designing particle physics comms for people who don't think about physics: the Urknall Unterwegs module

The Urknall Unterwegs module, a component of the outreach arm of the German science communication project KONTAKT, is a planned traveling indoor-outdoor exhibition on particle physics. Except it's intended for people who might not much care about physics. These are the people who skip the science centres, the open days at the local lab or institute, or who don't check into science documentaries on TV or YouTube. A team of science communicators, physicists, didactics experts, and lay people (i.e. unassuming test subjects) tried to figure out how best to talk to these people, bring the science to where they are, and make an experience that aims to get them thinking about why it's important to spend time and human effort on particle physics and basic research. We want a diverse group of people young and old to get inspired by how we research the basis of the world around them, while also showing the diversity of particle physics itself and how the field aspires to bring people from around the world together. I'd like to present the thinking behind the module's design and plans for its initial tour, which would begin in Fall 2021 (pandemic conditions permitting).

Speaker: Joseph Piergrossi (PR (Oeffentlichkeitsarbeit))

EPS-HEP_2021_UU_final.pdf

EPS-HEP_2021_UU_final.pptx

636 Particle Physics for Primary Schools: a Case Study about Science Teaching in K-12 Schools

We report on an ongoing project aimed to teach particle physics in primary schools, based on an original format developed by C.Lazzeroni and M.Pavlidou at the University of Birmingham (UK). The workshop allows young children (ages 8-11) to learn the world of particles, use creative design to make particle models and engage in creative writing to describe how particles interact with each other.
Early exposure to current results in contemporary science is important since it has been realized in recent years that children make decisions and choices about subjects they like during their primary school years.
We will start from the past and currently planned activities both in UK and in Italy in order to establish a broader framework to describe the conditions for the fruitful interplay between researchers and teachers in order to foster and support science outreach activities in schools.

Speaker: Andrea Quadri (INFN, Sez.di Milano)

talk.pdf

637 “Warning!”: from physics to an interdisciplinary project to discuss with students about the big planetary threats

The project “Warning! The big planetary threats: knowing them to defend ourselves " aimed to develop interdisciplinary educational paths on the themes of environmental fragility and dangerousness, addressing a wide audience but with a specific focus on young people.
The initiative consisted of 5 debates were scientists presented an in-depth scientific analysis of so-called natural disasters, i.e. phenomena related to climate change, major pandemics, endogenous events (i.e. volcanoes and earthquakes), the fall on the earth's surface of asteroids and space debris and finally to the pollution of the seas, and their consequences. The aim was to foster a “culture of being ready” consisting in the adoption of responsible and scientifically sound behaviors, overcoming a culture dominated by the 'here and now' and therefore little motivated to tackle long-term problems. All the considered phenomena have decidedly complex characteristics: the unpredictability or difficult predictability of their development, the quantification of the risks, the dangerous interconnections among them, the increasingly global nature of their effects and the diversity of their impact according to the social, economic and even cultural situations in the various geographical areas. The debates underlined the importance of internationally supportive initiatives to address these dangers. An interdisciplinary approach was used stressing the importance of the scientific method to face complex problems. Physics was the “fil rouge” accompanying the participants in this journey across many fields of science. The various events took place virtually, allowing the participation of more than 3000 high school students from about 20 schools. To encourage the conscious and direct participation of students in the debate, explanatory material provided in digital form was made available to interested teachers. Students were asked to present their questions to the speakers in advance, therefore a significant part of the seminars was devoted to answering student questions. "Warning" represented a useful educational support for students and teachers, who were able to attend the events in a 'virtual classroom', and integrate topics covered in school programs.

Speaker: Sandra Leone (INFN Pisa)

EPS-warning-Leone-Final2.pdf

638 Sharing ATLAS Science: communicating to the public

Communicating the science and achievements of the ATLAS Experiment is a core objective of the ATLAS Collaboration. This talk will explore the range of communication strategies adopted in ATLAS communications, with particular focus on how these have been impacted by the COVID-19 pandemic. In particular, an overview of ATLAS’ digital communication platforms will be given –with focus on social media –and the effect on target audiences evaluated with best practices are shared.

Speaker: Katarina Anthony (University of Udine)

SharingATLASScience-EPS2021-KAnthony.pdf

11:30 Lunch Break

ECFA Plenary

Convener: Karl Jakobs

639 Introduction

Speaker: Karl Jakobs

ECFA-EPS_2021.pdf

recording

640 Accelerator Roadmap

Speaker: David Newbold (STFC)

Accelerator_RD_210730.pdf

recording

641 Discussion

642 Detector Roadmap Status

Speaker: Phil Allport (University of Birmingham)

ECFA Detector R&D Roadmap EPS.pdf

recording

643 Discussion

14:15 Break

Plenary: EPS Poster Prize

Convener: Federico Antinori (INFN - Padova)

644 Introduction

Speaker: Federico Antinori (INFN - Padova)

recording

645 Poster prize talk: “New measurement of $\Lambda_c^+$ production in pp and p-Pb collisions with the ALICE experiment at the LHC”

Speaker: Clara Bartels (University of Liverpool)

2021-07-29-PosterTalk_v3.pdf

Poster

recording of prize talk

646 Poster prize talk: "Light dark matter searches with DarkMESA"

Speaker: Mirco Christmann

Poster

poster_award_presentation_christmann.pdf

recording of prize talk

647 Poster prize talk: "Bent crystals for investigation of the charmed baryons electromagnetic dipole"

Speaker: Marco Romagnoni (Univeresità degli Studi di Milano)

Poster

recording of prize talk

Romagnoni_talk_30-07-2021.pdf

Plenary Session 4

Conveners: Beate Heinemann (DESY and Freiburg University), Bostjan Golob, Val Gibson

648 Highlights from the BELLE II Experiment and Flavour Physics in e+e-

Speaker: Carsten Niebuhr (BELLE (BELLE Gruppe))

EPS-HEP Plenary Belle II Flavor.pdf

recording

649 Highlights from Neutrino Physics Experiments

Speaker: Prof. Christian Weinheimer (University of Muenster, Institut für Kernphysik)

recording

weinheimer_epshep_neutrino_final.pdf

650 Quark and Lepton Flavour Theory

Speaker: Ana Teixeira

Flavour_QL.AMT.EPS-30July2021.pdf

651 Future Collider Projects

Speaker: Lenny Rivkin (EPFL and PSI)

FutureColliders_LRivkin.pdf

recording

652 Conference Summary

Speaker: Florencia Canelli (University of Zurich)

EPS2021-final.pdf

recording

653 Closing remarks and invitation to EPS-HEP2023

Speakers: Johannes Haller (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik)), Matthias Schröder (Universität Hamburg), Thomas Gehrmann (University of Zurich), Ties Behnke (FLC (Forschung an Lepton Collidern))

EPS-HEP2021_Closing.pdf

recording