11th AxionWIMP conference (Patras workshop)
from
Monday, 22 June 2015 (08:00)
to
Friday, 26 June 2015 (18:10)
Monday, 22 June 2015
09:00
Inscription
Inscription
09:00 - 09:30
Room: Aula Magna
09:30
Welcome
Welcome
09:30 - 09:50
Room: Aula Magna
09:50
Review Indirect DM
-
Christoph Weniger
(
Postdoc
)
Review Indirect DM
Christoph Weniger
(
Postdoc
)
09:50 - 10:25
Room: Aula Magna
10:25
Cosmological search for ultra-light axions
-
Daniel Grin
(
University of Chicago, Kavli Institute for Cosmological Physics
)
Cosmological search for ultra-light axions
Daniel Grin
(
University of Chicago, Kavli Institute for Cosmological Physics
)
10:25 - 10:50
Room: Aula Magna
In today’s era of precision cosmology, we can go beyond cosmic accounting to actually testing various ideas for the identity of the dark matter and dark energy. One such idea is that the dark matter or even the dark energy is an ultra-light particle like an axion, the Goldstone boson of a new high-energy symmetry, motivated by the mystery of why charge-parity symmetry violation in the strong sector is so small. After reviewing the properties of the cosmic microwave background, I will discuss how we have tested the ultra-light axion idea using both cosmic microwave background fluctuations and the large-scale clustering of galaxies, putting constraints on ~7 orders of magnitude in axion mass. I will then discuss the prospects for future cosmological probes of axions and other light particles.
10:50
Coffe Break
Coffe Break
10:50 - 11:20
Room: Aula Magna
11:20
Dark matter searches with the LUX detector
-
Paolo Beltrame
(
University of Edinburgh
)
Dark matter searches with the LUX detector
Paolo Beltrame
(
University of Edinburgh
)
11:20 - 11:45
Room: Aula Magna
The Large Underground Xenon (LUX) experiment is a 350kg liquid xenon time projection chamber (TPC) designed to directly detect galactic dark matter. Currently deployed 1 mile underground in the Sanford Underground Research Facility in Lead, South Dakota, LUX completed its first physics run in 2013 collecting 85.3 live-days of science data. The profile-likelihood based analysis has shown no evidence for signal, setting the best limit on spin independent WIMP-nucleon cross section with a minimum of 7.6 × 10^-46 cm2 for WIMP mass of 33 GeV/c^2 at 90% CL. LUX is presently conducting a 300-day data set. We will present the present run status together with details of new calibrations and improvements to data analysis. Although optimised to detect weakly interacting massive particles, this Xe based TPC is particularly suitable for exploration of alternative dark matter scenarios - for example spin-dependent WIMP interaction, effective field theory approaches, axions and axion-like particles. The present status of these searches will also be presented.
11:45
IAXO
-
Javier Redondo
(
MPP & LMU
)
Biljana Lakic
(
Rudjer Boskovic Institute, Zagreb, Croatia
)
IAXO
Javier Redondo
(
MPP & LMU
)
Biljana Lakic
(
Rudjer Boskovic Institute, Zagreb, Croatia
)
11:45 - 12:10
Room: Aula Magna
12:10
Recent results from the EDELWEISS-III WIMP search experiment
-
Maryvonne De Jesus
(
IPNL
)
Recent results from the EDELWEISS-III WIMP search experiment
Maryvonne De Jesus
(
IPNL
)
12:10 - 12:35
Room: Aula Magna
The EDELWEISS experiment is dedicated to the direct detection of Dark Matter. The current setup – EDELWEISS-III – aims at exploring a spin-independent WIMP-nucleon cross section down to the 10^-9 pb range, and extend the coverage for masses below 20 GeV. Since July 2014, the collaboration is taking data with 24 state-of-the-art cryogenic FID800 Germanium detectors installed in the radio pure environment of the Modane underground laboratory - the deepest of its kind in Europe. In this talk I will present the current status of the EDELWEISS-III experiment and show first preliminary results highlighting our new low WIMP mass analysis and the current background budget.
12:35
CASPER
-
Alexander Sushkov
(
Hardvard University
)
CASPER
Alexander Sushkov
(
Hardvard University
)
12:35 - 13:00
Room: Aula Magna
13:00
Hints of ALPs from the sky?
-
maurizio giannotti
(
Barry Universtiy
)
Hints of ALPs from the sky?
maurizio giannotti
(
Barry Universtiy
)
13:00 - 13:25
Room: Aula Magna
I will review some of the recent bounds on axion-like particles (ALPs) from stellar evolution. In most cases, these bounds improved only marginally on the previous results, showing instead a little preference for new physics with couplings accessible by proposed experiments, particularly IAXO. I will briefly discuss the statistical significance of these hints and the need to understand better the source of possible systematics. Though individually each single hint is statistically weak, globally these results point to some particularly interesting regions in the ALP parameter space which could be accessed by the next generation ALP detectors.
13:25
Lunch Break
Lunch Break
13:25 - 15:00
Room: Aula Magna
15:00
Vector DM
-
Surjeet Rajendran
Vector DM
Surjeet Rajendran
15:00 - 15:35
Room: Aula Magna
15:35
Any Light Particle Search II
-
Noëmie Bastidon
(
Hamburg University
)
Any Light Particle Search II
Noëmie Bastidon
(
Hamburg University
)
15:35 - 16:00
Room: Aula Magna
Any Light Particle Search II (ALPS II) experiment (DESY, Hamburg) searches for photon oscillations into WISPs. This second generation of the ALPS light-shining-through-a-wall (LSW) experiment approaches the finalization of the preparation phase before ALPS IIa (search for hidden photons). In the last years, efforts have been put for the setting up of two optical cavities as well as characterization of a single-photon transition-edge sensor (TES) detector. Such detectors have showed excellent results in infrared single-photon detections with a detection efficiency higher than 95% and an intrinsic dark count rate of 1.0·10-4 sec-1 for 1064 nm photons. In parallel, the setting up of ALPS IIc (search for axion-like particles), including the unbending of 20 HERA dipoles, have been pursued. The latest progress in these tasks will be presented.
16:00
FUNK
-
Babette Doebrich
(
DESY
)
FUNK
Babette Doebrich
(
DESY
)
16:00 - 16:25
Room: Aula Magna
16:25
Proposal to detect axionic dark matter via their coherent interaction with intrinsic spin
-
Antonello Ortolan
(
INFN- Nat. Labs of Legnaro
)
Clive Speake
(
University of Birmingham
)
Proposal to detect axionic dark matter via their coherent interaction with intrinsic spin
Antonello Ortolan
(
INFN- Nat. Labs of Legnaro
)
Clive Speake
(
University of Birmingham
)
16:25 - 16:50
Room: Aula Magna
We present the research and development program that is underway at National Laboratories of Legnaro and University of Padova which aims to search for axionic dark matter in the range around 100 micro eV. The work is currently funded by INFN. We are investigating the possibility of exploiting the interaction of dark matter axions with the polarized spins in ferromagnetic or paramagnetic resonant systems. We briefly discuss the theoretical basis of this approach, the expected signal to noise ratio and the potential for detection of such a scheme. We hope to be able to present our preliminary experimental work at the time of the conference.
16:50
Poster Session and Reception
Poster Session and Reception
16:50 - 18:50
Room: Aula Magna
Tuesday, 23 June 2015
09:00
Self interacting DM review
-
Sean Tulin
(
York University
)
Self interacting DM review
Sean Tulin
(
York University
)
09:00 - 09:35
Room: Aula Magna
09:35
Using an InGrid-Detector to search for solar axions and chameleons
-
Klaus Desch
(
University of Bonn
)
Using an InGrid-Detector to search for solar axions and chameleons
Klaus Desch
(
University of Bonn
)
09:35 - 10:00
Room: Aula Magna
We report on recent results from the application of InGrids in the CAST experiment at CERN searching for solar axions and solar chameleons. InGrids employ Micromegas-like gas amplification using a highly pixellated CMOS readout chip as charge-collecting anode. An InGrid detector has successfully taken data in the CAST setup using the Abrixas X-ray telescope in late 2014. Operation experience and first results from this data taking period will be presented. A multi-variate technique for background reduction will be shown. An outlook will be given towards further improvements of the setup in terms of X-ray efficiency and active background suppression. Also, potential application of InGrids as X-ray detectors in IAXO will be discussed.
10:00
Theoretical prospects for directional dark matter detection
-
Ciaran O'Hare
(
University of Nottingham
)
Theoretical prospects for directional dark matter detection
Ciaran O'Hare
(
University of Nottingham
)
10:00 - 10:25
Room: Aula Magna
Direct detection of WIMPs where the direction of nuclear recoils is measured presents an exciting opportunity for studying the physics and astrophysics of WIMPs. Additionally, directionality offers crucial information that distinguishes a WIMP signal from the irreducible background to direct detection, neutrinos. I will describe work assessing the theoretical capabilities of future generations of directional detectors including searching for non-standard velocity distributions of WIMPs in the Milky Way and how directional detectors can help circumvent the encroaching neutrino floor.
10:25
Last results from the OSQAR experiment for the search of Axion like particle and short term perspective for Chameleons
-
Miroslav Sulc
(
Technical University of Liberec
)
Last results from the OSQAR experiment for the search of Axion like particle and short term perspective for Chameleons
Miroslav Sulc
(
Technical University of Liberec
)
10:25 - 10:50
Room: Aula Magna
The last results and near future plans of the OSQAR experiment at the low energy frontier, i.e. sub-eV range, will be presented. The OSQAR-LSW experiment dedicated to axion like particle search from Light Shining through Wall have been run in 2014 with an unprecedented sensitivity using two spare LHC dipole. The number of incident photons as well as the photon detection efficiency has been increased by using an 18.5 W DC laser and a state-of-the art CCD, respectively. Moreover a new statistical data analysis has been developed. All these improvements have led to new exclusion limits for the di-photon couplings for both scalar and pseudo-scalar particles. The OSQAR-CHASE experiment will look for chameleons, i.e. particles with environment-dependent mass, from the search of a magnetic afterglow effect due to the possible coupling of chameleons to photons. Simulation results from the preparatory phase as well as preliminary data will be presented.
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula Magna
11:20
The DEAP-3600 Search for Dark Matter
-
Alistair Butcher
(
Royal Holloway - University of London
)
The DEAP-3600 Search for Dark Matter
Alistair Butcher
(
Royal Holloway - University of London
)
11:20 - 11:45
Room: Aula Magna
DEAP-3600 is a single phase dark matter direct detection experiment at SNOLAB, Ontario, Canada. DEAP-3600 has been designed to achieve extremely low background rates, including those from 39Ar β decays, neutron scatters, and surface α contamination, with the goal of measuring the spin-independent WIMP-nucleon cross section down to 1E−46 cm^2 for a 100 GeV WIMP. An overview of the experiment will be presented with updates on the current status of calibration and data taking.
11:45
Cavity-based Axion and WISP experiments at the University of Western Australia
-
Michael Tobar
(
The University of Western Australia
)
Cavity-based Axion and WISP experiments at the University of Western Australia
Michael Tobar
(
The University of Western Australia
)
11:45 - 12:10
Room: Aula Magna
We report on the progress of attempting to verify recent claims of a possible 0.11 meV axion signal (~26 GHz) and discuss the feasibility of using readily available tools to perform a very narrowband Haloscope-style experiment to check for such an axion signal. Also, we outline the principles of the cross-spectrum measurement technique whereby two spectrums are cross-correlated together, allowing for rejection of uncorrelated noise processes. We apply these concepts to microwave cavity-based searches for axions, such as the Haloscope style experiment, and WISPs, such as hidden sector photon light-shining-through-a-wall. We discuss how such techniques can be used to enhance these experiments.
12:10
Status of preparations for the Phase II of the GERDA experiment aimed for the 0νββ decay search
-
Alexey Lubashevskiy
(
Max-Planck-Institut für Kernphysik
)
Status of preparations for the Phase II of the GERDA experiment aimed for the 0νββ decay search
Alexey Lubashevskiy
(
Max-Planck-Institut für Kernphysik
)
12:10 - 12:35
Room: Aula Magna
GERDA is a low background experiment aimed for the neutrinoless double beta-decay search. It is located at the LNGS underground laboratory of INFN in Italy. The search is performed using high purity germanium detectors operated in liquid argon (LAr) that are enriched enriched in 76Ge to 86%. The backgrounds from the detector’s surrounding are reduced to a background index of 10^−2 cts/(keV•kg•yr). This is about one order of magnitude better than in predecessor experiments with HPGe detectors. Accumulated statistics allows to derive the most stringent lower limit on the half-life for neutrinoless double beta-decay decay of 76Ge: 2.1•10^25 yr. Currently the preparations for Phase II are ongoing. A LAr scintillation veto has been installed in GERDA. 20 kg of new type BEGe detectors with powerful pulse shape discrimination ability and better energy resolution will be incorporated in the setup soon. We expect that the use of the new active background reduction techniques and cleaner materials would allow us to achieve background index of 10^−3 cts/(keV•kg•yr) and significantly increase the sensitivity of the experiment. The actual status of the experiment will be presented.
12:35
Mixed axion/axino dark matter in R-parity violating Supersymmetry and X-ray lines
-
Stefano Colucci
(
Universität Bonn
)
Mixed axion/axino dark matter in R-parity violating Supersymmetry and X-ray lines
Stefano Colucci
(
Universität Bonn
)
12:35 - 13:00
Room: Aula Magna
The axion is a well-known cold dark matter (CDM) candidate. Its fermionic partner in supersymmetry, the axino, can also be stable on cosmological times and if its mass is of order keV, if it is a warm dark matter (WDM) candidate. Assuming that the Peccei-Quinn (PQ) phase transition happens after the end of inflation, the mixed axion CDM / axino WDM scenario can only be realized for $10^{10} < f_a/{\rm GeV} < 10^{11}$, with $f_a$ the PQ scale. This combination is particularly interesting in the context of R-parity violating (RPV) supersymmetric models for two reasons: (a) they would otherwise lack a dark matter candidate, and (b) the keV axino can decay, with a lifetime much longer than the age of the universe, into a photon and a neutrino and produce an X-ray signal. In this work, we study a supersymmetric model with a baryon triality discrete symmetry, in which we introduce a DFSZ axion superfield. We embed the model in supergravity, parametrize supersymmetry breaking with soft terms, determine under which conditions the model is cosmologically acceptable and provide three benchmark points which would result in potentially detectable X-ray lines from axino decays.
13:00
Light Dark Matter in the NOvA Near Detector, a first look at the new data.
-
Athanasios Hatzikoutelis
(
University of Tennessee
)
Light Dark Matter in the NOvA Near Detector, a first look at the new data.
Athanasios Hatzikoutelis
(
University of Tennessee
)
13:00 - 13:25
Room: Aula Magna
The neutrino oscillations experiment NOvA is the flagship of Fermi National Laboratory. The neutrino source NuMI is delivering record numbers of protons-on-target surpassing the most stringent dark matter production upper limits of current models in the under-10 GeV mass range. We take advantage of the sophisticated particle identification algorithms of the experiment to interrogate the data from the 300-ton, off-axis, low-Z, Near Detector of NOvA during the experiment’s first physics runs. We search for signatures of Dark Matter, Axion-like-particles, and Heavy or Sterile Neutrino that may scatter or decay in the volume of the detector.
13:25
Lunch Break
Lunch Break
13:25 - 15:00
Room: Aula Magna
15:00
WIMP Review
-
David Cerdeño
(
IPPP, Durham University
)
WIMP Review
David Cerdeño
(
IPPP, Durham University
)
15:00 - 15:35
Room: Aula Magna
15:35
Axions and CMB spectral distortions in cosmic magnetic field
-
Damian Ejlli
(
Laboratori Nazionali del Gran Sasso
)
Axions and CMB spectral distortions in cosmic magnetic field
Damian Ejlli
(
Laboratori Nazionali del Gran Sasso
)
15:35 - 16:00
Room: Aula Magna
I will discuss the impact of photon-axion mixing on distorting the CMB spectrum. Limits on the axion mass and stochastic magnetic fields are discussed.
16:00
Indirect dark matter searches with MAGIC telescopes
-
Konstancja Satalecka
(
UCM, Spain
)
Indirect dark matter searches with MAGIC telescopes
Konstancja Satalecka
(
UCM, Spain
)
16:00 - 16:25
Room: Aula Magna
A major open question for modern physics is the nature of dark matter: strong experimental evidences suggest the presence of this elusive component in the energy budget of the Universe, without, however, being able to provide conclusive results about its nature. In the last few years the indirect DM searches became a hot topic, with several experimental results (e.g. Fermi, PAMELA) showing hints of DM signal. The Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes are two 17 m diameter Cherenkov telescopes, located on the Canary island La Palma (Spain), with an optimal view on the Northern sky. It is nowadays one of the few ground-based instruments able to measure high-energy gamma-rays below 100 GeV. MAGIC carries out a broad DM search program, including observations of dwarf galaxies, galaxy clusters and other DM dominated objects. In this talk we will present recent MAGIC results in this field. We will discuss them in a broader context, giving an brief overwiev of the present and future of DM searches with Cherenkov telescopes.
16:25
A proposal to search for a “dark-omega” vector boson in direct electro-production processes using intense high energy electron beams
-
Ashot Gasparian
(
NC A&T State University
)
A proposal to search for a “dark-omega” vector boson in direct electro-production processes using intense high energy electron beams
Ashot Gasparian
(
NC A&T State University
)
16:25 - 16:50
Room: Aula Magna
We propose to perform new experiments to search for a new vector boson coupled via baryonic current (“dark-omega”) in the mass range of [150-600] MeV. This particle, if it exists in nature, will be produced on large-A fixed targets in the forward direction using electron beams with energies up to 11.5 GeV. High intensity and high energy electron beams are well suited for this type of search experiments. The multi-gamma decay of this, yet unknown, particle (VB→π0γ→γγγ) can be detected by a high resolution and large acceptance crystal calorimeter (like the existing PrimEx HyCal PbWO4 calorimeter at Jefferson Lab). That will provide a few MeV level resolutions in the proposed multi-photon invariant mass reconstruction process. In this talk the motivation, feasibility studies of the setup and estimation of the realistic parameter space of the proposed experiment will be presented and discussed.
16:50
Coffee Break
Coffee Break
16:50 - 17:15
Room: Aula Magna
17:15
Second Stage of WISPDMX Measurements
-
Andrei Lobanov
(
University of Hamburg
)
Second Stage of WISPDMX Measurements
Andrei Lobanov
(
University of Hamburg
)
17:15 - 17:35
Room: Aula Magna
Weakly interactive slim particles (WISP), including the QCD axion, axion-like particles (ALP), and hidden photon, are considered to be strong candidates for the dark matter carrier particle. The microwave cavity experiment WISPDMX is the first direct WISP dark matter search experiment probing the particle masses in the 0.8-2.0 micro-eV range. The first stage of WISPDMX measurements made at nominal resonant frequencies of the cavity constrains the kinetic mixing angle of hidden photons well inside the region of the parameter space where hidden photons can constitute the dark matter. The second and third stages of WISPDMX are presently being prepared. At these stages, WISPDMX will employ cavity tuning and a strong magnet to probe up to 80% of the 0.8--2 micro-eV range and to extend the searches also to axions. The results from the first stage of WISPDMX measurements and the preparations for the successive stages will be described.
17:35
Running in the Dark Sector
-
Hooman Davoudiasl
(
BNL
)
Running in the Dark Sector
Hooman Davoudiasl
(
BNL
)
17:35 - 17:55
Room: Aula Magna
The dark photon can become effectively invisible if it primarily decays into light dark matter states. Such a scenario may allow for production and detection of these states at fixed target experiments. We point out that in the presence of the light states, the dark U(1) coupling constant may exhibit significant running, as a function of momentum transfer, over the kinematic range of the experiments. In typical models, an associated running is also induced in the kinetic mixing parameter that connects the dark and the visible sectors. The combined running of these parameters could probe the spectrum of light dark particles and also substantially modify some existing predictions for the above experiments. We also outline theoretical considerations that can imply upper bounds on the low energy value of the dark U(1) coupling.
17:55
Parameters of the astrophysically motivated axion-like particle.
-
Sergey Troitsky
(
INR, Moscow
)
Parameters of the astrophysically motivated axion-like particle.
Sergey Troitsky
(
INR, Moscow
)
17:55 - 18:15
Room: Aula Magna
Recent astrophysical results suggest that axion-like particles (ALPs) may be favored by the observational data. We give a quantitative comparison of various ALP scenarios, in view of astrophysical data, determine favored regions in the ALP parameter space and outline future observations which may help to distinguish between scenarios.
18:15
Astrophysical constraints to axion-photon coupling
-
Oscar Straniero
(
INA
)
Astrophysical constraints to axion-photon coupling
Oscar Straniero
(
INA
)
18:15 - 18:35
Room: Aula Magna
We revise the astrophysical bound to the axion-photon coupling, as obtained by comparing R=N_HB/N_RGB (1) measured in a sample of 39 Galactic Globular Clusters with up-to-date theoretical predictions. First results, already published in a PRL paper in 2014, show that the derived bound significantly depends on the assumed He mass fraction. To remove this degeneracy, accurate measurements of the early He content of our Galaxy are required. More recently, we have developed a new and more accurate method to calculate the theoretical R, which makes use of synthetic Colour-Magnitude diagrams to be directly compared to the observed (real) diagrams. It required the calculation of a few hundreds evolutionary sequences of stellar models with the typical mass of the evolved stars in Globular Clusters, under various assumptions for the original He content and mass loss history. Uncertainties in the relevant nuclear reaction rates, as well as those related to the development of convection during the core He burning phase, have been carefully considered and combined by means of a Monte Carlo procedure. Methods and results of this new analysis will be here presented.
18:35
ALPs explain the unphysical redshift-dependence of blazar spectra
-
Marco Roncadelli
(
INFN - Pavia
)
ALPs explain the unphysical redshift-dependence of blazar spectra
Marco Roncadelli
(
INFN - Pavia
)
18:35 - 19:00
Room: Aula Magna
So far about 41 blazars have been detected with the IACTs and their emitted energy spectra analyzed. They differ from the observed ones because of photon absorption due to the EBL. It turns out that the most energetic emitted spectra belong to the most distant blazars, and so their lack at smaller distances looks unphysical, since no conventional explanation works. Yet, the existence of ALPs yields a simple way out of this conundrum for realistic values of the model parameters, provided they oscillate to photons in extragalactic magnetic fields in the 0.1 nG range. As a consequence, blazars with very energetic emitted spectra are present at any distance, as naturally expected. Remarkably, for the same choice of the ALP properties also two other puzzling astrophysical effects are naturally explained. Both ALPS II and the CTA will be able to check our prediction.
Wednesday, 24 June 2015
08:00
Visit to Canfranc and Undergroudn Lab
Visit to Canfranc and Undergroudn Lab
08:00 - 14:00
Room: Edificio sede
14:00
Axion NMR experiment
-
Andy Geraci
Axion NMR experiment
Andy Geraci
14:00 - 14:35
Room: Edificio sede
14:35
Status of the ANAIS dark matter project at the Canfranc underground laboratory
-
Miguel Ángel Olivan
(
Universidad de Zaragoza
)
Status of the ANAIS dark matter project at the Canfranc underground laboratory
Miguel Ángel Olivan
(
Universidad de Zaragoza
)
14:35 - 15:00
Room: Edificio sede
The ANAIS (Annual Modulation with NaI(Tl) Scintillators) experiment aims at the confirmation of the DAMA/LIBRA signal using the same target and technique at the Canfranc Underground Laboratory. Two NaI(Tl) crystals of 12.5 kg each, grown by Alpha Spectra from a powder having a potassium level under the limit of the analytical techniques, form the ANAIS-25 set-up. A detailed analysis of ANAIS-25 data will be presented: MC simulations reproduce very satisfactorily the measured background, effective threshold at 1 keVee is at reach, robust PMT noise filtering protocols have been developed, the bulk content in the crystals of potassium as well as of uranium and thorium radioactive chains has been quantified and cosmogenic activation of NaI(Tl) has been evaluated for the first time. Very preliminary results of a new 12.5 kg NaI(Tl) detector, received at LSC in the first week of March 2015, and installed together with the two previous modules forming the ANAIS37 set-up, will be presented. Finally, background prospects and expected sensitivity for the set-up with 250 kg will be shown and the status of the full ANAIS experiment will be reviewed.
15:00
Experimental efforts at CAPP related to the axion issues and the strong CP problem
-
Yannis Semertzidis
(
CAPP/IBS and KAIST
)
Experimental efforts at CAPP related to the axion issues and the strong CP problem
Yannis Semertzidis
(
CAPP/IBS and KAIST
)
15:00 - 15:25
Room: Edificio sede
The Center for Axion and Precision Physics research (CAPP) of the Institute for Basic Science (IBS) at the KAIST campus of South Korea is making a comprehensive effort towards resolving the issues related to axions and the strong CP-problem. Already a number of projects are either in the construction phase or in the design phase, promising an exciting decade in axion physics. I will provide an overview of the experiments under preparation by CAPP scientists.
15:25
Composite Dark Sectors
-
Adrian Carmona
(
ETH Zürich
)
Composite Dark Sectors
Adrian Carmona
(
ETH Zürich
)
15:25 - 15:50
Room: Edificio sede
We introduce a new paradigm in Composite Dark Sectors, where the full Standard Model (including the Higgs boson) is extended with a strongly-interacting composite sector with global symmetry group G spontaneously broken to H⊂G. We show that, under well-motivated conditions, the lightest neutral pseudo Nambu-Goldstone bosons are natural dark matter candidates for they are protected by a parity symmetry not even broken in the electroweak phase. These models are characterized by only two free parameters, namely the typical coupling gD and the scale fD of the composite sector, and are therefore very predictive. We consider in detail two minimal scenarios, SU(3)/[SU(2)×U(1)] and [SU(2)×SU(2)xU(1)]/[SU(2)×U(1)], which provide a dynamical realization of the Inert Doublet and Triplet models, respectively. We show that the radiatively-induced potential can be computed in a five-dimensional description with modified boundary conditions with respect to Composite Higgs models. Finally, the dark matter candidates are shown to be compatible, in a large region of the parameter space, with current bounds from dark matter searches as well as electroweak and collider constraints on new resonances.
15:50
Coffee Break
Coffee Break
15:50 - 16:20
Room: Edificio sede
16:20
New axion and hidden photon constraints from a solar data global fit
-
Núria Vinyoles Vergés
(
Institute of Space Sciences (CSIC-IEEC)
)
New axion and hidden photon constraints from a solar data global fit
Núria Vinyoles Vergés
(
Institute of Space Sciences (CSIC-IEEC)
)
16:20 - 16:40
Room: Aula Magna
I will present the results of a our last paper that presents a new statistical analysis that combines helioseismology sound speed,surface helium and convective radius) and solar neutrino observations (boron and beryllium fluxes) to place upper limits to the properties of non standard weakly interacting particles. Our analysis includes theoretical and observational errors, accounts for tensions between input parameters of solar models and can be easily extended to include other observational constraints. We present two applications to test the method: the well studied case of axions and axion-like particles and the more novel case of low mass hidden photons. For axions we obtain an upper limit at 3σ for the axion-photon coupling constant of gaγ<4·10−10 GeV−1. For hidden photons we obtain the most restrictive upper limit for the product of the kinetic mixing and mass of χm < 1.82·10−12 eV at 3σ. Both cases improve the previous solar constraints based on the Standard Solar Models showing the power of our global statistical approach.
16:40
Exploring dark matter with AMS through electroweak corrections
-
Mathieu Pellen
(
RWTH Aachen
)
Exploring dark matter with AMS through electroweak corrections
Mathieu Pellen
(
RWTH Aachen
)
16:40 - 17:05
Room: Edificio sede
The AMS experiment is now measuring charged cosmic rays fluxes with an unprecedented precision. It is thus necessary to provide appropriate predictions for dark matter signals. To that end, computing electroweak corrections is an important task. It is particularly relevant for leptophilic models where anti-protons can be produced through the decay of massive gauge bosons. In this talk, we present a new calculation of electroweak radiation for vector dark matter annihilation. From the lack of particular spectral features in the AMS positron flux, we derive upper limits on the annihilation cross section. We furthermore provide predictions for the flux of anti-protons from electroweak radiation, which will be probed by AMS in the future.
17:05
Comissioning of TREX-DM, a low background Micromegas-based TPC for low mass WIMP detection
-
Francisco Jose Iguaz Gutierrez
(
University of Zaragoza
)
Comissioning of TREX-DM, a low background Micromegas-based TPC for low mass WIMP detection
Francisco Jose Iguaz Gutierrez
(
University of Zaragoza
)
17:05 - 17:30
Room: Edificio sede
Dark Matter experiments are recently focusing their detection techniques in low-mass WIMPs, which requires the use of light elements and low energy threshold. In this context, we describe the TREX-DM experiment, a low background Micromegas-based TPC for low-mass WIMP detection. Its main goal is the operation of an active detection mass ∼0.300 kg, with an energy threshold below 0.4 keVee and fully built with previously selected radiopure materials. This work focus on the commissioning of the actual setup situated in a laboratory on surface. We also describe the updates needed for a possible physics run at the Canfranc Underground Laboratory in 2016. A preliminary background model of TREX-DM is also presented, based on Geant4 simulations and two discrimination methods: a conservative muon/electron and one based on a 252Cf source. Based on this background model, TREX-DM could be competitive in the search for low mass WIMPs. In particular it could be sensitive, e.g., to the low mass WIMP interpretation of the DAMA/LIBRA and other hints in a conservative scenario.
17:30
Axion search and research with low background Micromegas
-
Juan Antonio García Pascual
(
Universidad de zaragoza
)
Axion search and research with low background Micromegas
Juan Antonio García Pascual
(
Universidad de zaragoza
)
17:30 - 17:55
Room: Edificio sede
Helioscopes are one of the most promising techniques for axion discovery in which low background x-ray detectors are mandatory. We report the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST). The use of low background techniques has led to background levels below $10^{−6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors at CAST. The helioscope technique can be enhanced by the use of an x-ray focusing device, increasing the signal-to-background ratio. A new dedicated x-ray optic was installed at CAST during 2014 with a low background Micromegas in its focal plane. On top of increasing CAST’s sensitivity, the system has been conceived as a technological pathfinder for the International Axion Observatory IAXO.
17:55
Unconventional ideas for axion and DM experiments
-
Fritz Caspers
Unconventional ideas for axion and DM experiments
Fritz Caspers
17:55 - 18:02
Room: Edificio Sede
Thursday, 25 June 2015
09:00
The meV frontier of axion physics
-
Georg Raffelt
(
MPP Munich
)
The meV frontier of axion physics
Georg Raffelt
(
MPP Munich
)
09:00 - 09:35
Room: Aula Magna
09:35
Status of the CRESST-II Experiment for Direct Dark Matter Search
-
Andrea Muenster
(
TU Muenchen
)
Status of the CRESST-II Experiment for Direct Dark Matter Search
Andrea Muenster
(
TU Muenchen
)
09:35 - 10:00
Room: Aula Magna
The direct dark matter search experiment CRESST-II uses scintillating CaWO4 single crystals as targets for possible scattering of Weakly Interacting Massive Particles (WIMPs). The simultaneous measurement of scintillation light and phonons produced in the crystal by a particle interaction allows a suppression of most of the background. Most of the remaining background in the previous phase 1 (2009-2012, G. Angloher et al., Eur. Phys. J. C v.72 nr4 (2012)) originated from alpha-decays in non-scintillating materials in the vicinity of the CaWO4 crystals. Therefore, in the currently ongoing phase 2 six detector modules equipped with an active veto for such events are installed. In this contribution we will present the results achieved by one of these fully scintillating detector modules using 29 kg days of data taken in 2013 (G. Angloher et al., Eur. Phys. J. C v.74 nr.12 (2014)). A new limit on the elastic WIMP-nucleon scattering cross-section for WIMPs lighter than 3GeV/c^2 could be set. The upcoming experiment CRESST-III will focus on the investigation of the low-mass WIMP regime. The status of the preparations and prospects for CRESST-III will be presented.
10:00
Axion BEC?
-
Chanda Prescod-Weinstein
Axion BEC?
Chanda Prescod-Weinstein
10:00 - 10:25
Room: Aula Magna
10:25
Status of the Axion Dark Matter Experiment (ADMX)
-
Gray Rybka
(
University of Washington
)
Status of the Axion Dark Matter Experiment (ADMX)
Gray Rybka
(
University of Washington
)
10:25 - 10:50
Room: Aula Magna
The Axion Dark Matter Experiment (ADMX) is a search for QCD axion dark matter using axion-photon conversion in a resonant cavity. The "Gen 2" version of ADMX, presently in commissioning, improves upon previous versions using a dilution refrigerator, enhancing sensitivity to be sensitive to even pessimistically coupled DFSZ axions. I will present the status of the commissioning, plans for the upcoming data run plan, our strategy to expand the search to higher masses, and ongoing R&D to improve sensitivity.
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula Magna
11:20
Axion and baryogenesis
-
Geraldine Servant
Axion and baryogenesis
Geraldine Servant
11:20 - 11:45
Room: Aula Magna
11:45
The Coldest Axion Experiment at CAPP/IBS/KAIST in Korea
-
Woohyun Chung
(
CAPP/IBS
)
The Coldest Axion Experiment at CAPP/IBS/KAIST in Korea
Woohyun Chung
(
CAPP/IBS
)
11:45 - 12:10
Room: Aula Magna
The axion, a hypothetical elementary particle arising from Peccei-Quinn solution to the strong-CP problem, is a well-motivated dark matter candidate. The IBS Center for Axion and Precision Physics (CAPP) in Korea will explore the dark matter axion using a method suggested by P. Sikivie, converting the axions into microwave photons in a resonant cavity permeated by a strong magnetic field. CAPP’s first microwave axion experiment in an ultra-low temperature setup is being launched at KAIST (Korea Advanced Institute of Science and Technology) campus this summer, utilizing top of the line equipment and technology. I will discuss the progress and future plans of the axion experiment.
12:10
SuperCDMS
-
Paul Brink
(
SLAC
)
SuperCDMS
Paul Brink
(
SLAC
)
12:10 - 12:35
Room: Aula Magna
12:35
Atomic Methods for Axion and WIMP Detection
-
Benjamin Roberts
(
University of New South Wales
)
Atomic Methods for Axion and WIMP Detection
Benjamin Roberts
(
University of New South Wales
)
12:35 - 13:00
Room: Aula Magna
We present our recent proposals to exploit the parity and time-reversal violating effects in atoms, nuclei, and molecules to search for evidence of various background cosmic fields, and to constrain the interaction strengths of these fields with fermions. Candidates for such background fields include dark matter (e.g. axions) and dark energy, and also are motivated by various Standard Model extensions. Certain interactions of static and dynamic background cosmic fields would lead to the mixing of opposite parity states in atoms and molecules. This would, in turn, give rise to observable parity and time-invariance violating effects. The measurement of such effects would shed light on the interactions that gave rise to them. Of particular interest is the interaction of a dynamic pseudoscalar field with atomic/molecular electrons and nuclei. Such a field could describe axions, a hypothetical pseudoscalar particle invoked to solve the strong CP problem from QCD, now also a leading cold dark matter candidate. We perform calculations of the parity and time-invariance violating effects that such a field would induce in atoms [1,2], and demonstrate a potential very large enhancement of the effects in diatomic molecules. Crucially, the effects we consider here are linear in the small parameter that quantifies the interaction strength between the dark matter particles and ordinary matter particles; most current dark matter and axion searches rely on effects that are proportional to quadratic and higher powers of this parameter. Oscillating electric dipole moments have the potential to be measured with very high accuracy, and experimental techniques in this field are evolving fast, making this a particularly exciting area for potential discovery in the near future. Pairs of closely spaced opposite parity levels that are found in diatomic molecules may also lead to a significant enhancement in these effects [2,3]. We are also investigating a possible explanation for the DAMA annual modulation result - a 9 sigma result claimed to be a detection of WIMP dark matter. This result is controversial, however, because of null results of several other experiments. The DAMA experiment is sensitive to scattering off both electrons and nuclei. Most other DM detection experiments, however, reject pure electron events, meaning that DM particles that interact favorably with electrons could potentially explain the DAMA modulation without being ruled out by the other null results. We perform accurate relativistic Hartree-Fock atomic calculations to determine model-independent cross-sections and event rates for the atomic ionization induced by the interaction with dark matter for xenon, iodine, and sodium. Our results have implications for the interpretation of the DAMA annual modulation signal in terms of WIMP–electron scattering. 1. B. M. Roberts, Y. V. Stadnik, V. A. Dzuba, V. V. Flambaum, N. Leefer, and D. Budker. Limiting P-Odd Interactions of Cosmic Fields with Electrons, Protons, and Neutrons. Phys. Rev. Lett. 113, 081601 (2014). 2. B. M. Roberts, Y. V. Stadnik, V. A. Dzuba, V. V. Flambaum, N. Leefer, and D. Budker. Parity-violating interactions of cosmic fields with atoms, molecules, and nuclei: Concepts and calculations for laboratory searches and extracting limits [Editors' Suggestion]. Phys. Rev. D 90, 096005 (2014). 3. Y. V. Stadnik, and V. V. Flambaum. Axion-induced effects in atoms, molecules, and nuclei: Parity nonconservation, anapole moments, electric dipole moments, and spin-gravity and spin-axion momentum couplings. Phys. Rev. D, 89, 043522 (2014).
13:00
Cold and ultra-cold Neutrons: Gravity Resonance Spectroscopy Constrain Dark Matter and Dark Enery Scenarios
-
Abele
Cold and ultra-cold Neutrons: Gravity Resonance Spectroscopy Constrain Dark Matter and Dark Enery Scenarios
Abele
13:00 - 13:25
Room: Aula Magna
13:25
Lunch Break
Lunch Break
13:25 - 15:00
Room: Aula Magna
15:00
Review DM at colliders
-
Jalal Abdallah
Review DM at colliders
Jalal Abdallah
15:00 - 15:35
Room: Aula Magna
15:35
A simplified model interpretation of searches for dark matter at the LHC and with the IceCube Neutrino Observatory
-
Jan Heisig
(
RWTH Aachen University
)
A simplified model interpretation of searches for dark matter at the LHC and with the IceCube Neutrino Observatory
Jan Heisig
(
RWTH Aachen University
)
15:35 - 16:00
Room: Aula Magna
We present an interpretation of searches for dark matter in a simplified model approach. Considering Majorana fermion dark matter and neutral vector mediators with axial-vector interaction we compare the limits obtained in mono-jet searches at the LHC with limits on the spin-dependent scattering cross-section set by the IceCube collaboration. We discuss the dependence of the search sensitivity to the mediator mass and place new limits on the parameter space of this model.
16:00
Supernovae WISP bounds
-
Alessandro Mirizzi
(
DESY
)
Supernovae WISP bounds
Alessandro Mirizzi
(
DESY
)
16:00 - 16:25
Room: Aula Magna
16:25
Bose-Einstein Condensation of Dark Matter Axions
-
Pierre Sikivie
(
University of Florida
)
Bose-Einstein Condensation of Dark Matter Axions
Pierre Sikivie
(
University of Florida
)
16:25 - 16:50
Room: Aula Magna
It has long been known that axions produced by vacuum realignment during the QCD phase transition in the early universe form a cold degenerate Bose gas and are a candidate for the dark matter. More recently it was found that dark matter axions thermalize through their gravitational self-interactions and form a Bose-Einstein condensate (BEC). On time scales long compared to their rethermalization time scale, almost all the axions go to the lowest energy state available to them. In this behaviour they differ from the other dark matter candidates. Axions accreting onto a galactic halo fall in with net overall rotation because almost all go to the lowest energy available state for given angular momentum. In contrast, the other proposed forms of dark matter accrete onto galactic halos with an irrotational velocity field. The inner caustics are different in the two cases. I'll argue that the dark matter is axions because there is observational evidence for the type of inner caustic produced by, and only by, an axion BEC.
16:50
Coffee Break
Coffee Break
16:50 - 17:20
Room: Aula Magna
17:20
Laboratory Search for New Spin-Dependent Interaction : Axion Resonant Interaction Detection Experiment (ARIADNE)
-
YUNCHANG SHIN
(
CENTER FOR AXION AND PRECISION PHYSICS RESEARCH (CAPP) /INSTITUTE FOR BASIC SICENCE (IBS)
)
Laboratory Search for New Spin-Dependent Interaction : Axion Resonant Interaction Detection Experiment (ARIADNE)
YUNCHANG SHIN
(
CENTER FOR AXION AND PRECISION PHYSICS RESEARCH (CAPP) /INSTITUTE FOR BASIC SICENCE (IBS)
)
17:20 - 17:40
Room: Aula Magna
Axions are light pseudoscalar particles originally proposed by Peccei and Quinn (PQ) to explain the strong CP problem in QCD [1]. Axions could be a possible component of cold dark matter if their mass is in very light regime. Direct search of axions dark matter is the object of current experiment at the Center for Axion and Precision Physics (CAPP), Institute for Basic Science (IBS). This experiment involves axion to photon conversion in a resonant cavity [2]. In addition, Axions and other axion-like particles (ALP) would mediate spin-dependent interactions in macroscopic scale [3]. A precision experiment that can detect axions by measuring spin-dependent interactions in very short range has been recently proposed from ARIADNE collaboration [4]. The experiment includes high sensitivity SQUID NMR with polarized $^{3}$He nuclei using the metastability-exchange optical pumping (MEOP) method and a radially slotted tungsten as unpolarized source mass to induce a resonant monopole-dipole interaction. With proper magnetic shielding, it will resonantly enhance the effective magnetic field signal from the spin-dependent interaction mediated by axion. The proposed experiment can look into axions in their mass range between $10^{-5}$ eV to $10^{-2}$ eV which is very complementary with our experimental search of axions with resonant cavity. We describe the experimental plan including $^{3}$He optical pumping system at CAPP, IBS. [1] R. D. Peccei and H. R. Quinn, Phys. Rev. Lett. 38, 1440 (1977). [2] P. Sikivie, Phys. Rev. Lett, 51,1415, (1983). [3] J. E. Moody and F. Wilczek, Phys. Rev. D 30, 130 (1984). [4] A. Arvanitaki and A. Geraci, Phys. Rev. Lett. 113, 161801 (2014).
17:40
Hidden photon CDM search at Tokyo
-
Jun'ya Suzuki
(
Department of Physics, School of Science, The University of Tokyo
)
Hidden photon CDM search at Tokyo
Jun'ya Suzuki
(
Department of Physics, School of Science, The University of Tokyo
)
17:40 - 18:00
Room: Aula Magna
We report on a search for hidden photon cold dark matter (HP CDM) using a novel technique with a dish antenna. We constructed two independent apparatus: one is aiming at the detection of the HP with a mass of $\sim5\times10^{-5}\,\rm{eV}$ utilizing a commercially available parabolic antenna facing on a plane reflector, and the other is for a mass of $\sim\,\rm{eV}$ which employs optical instruments. From the result of the measurement, we found no evidence for the existence of HP CDM and set upper limits on the photon-HP mixing parameter $\chi$.
18:00
Conecting the Inverse Seesaw Mechanism to a Symmetry Breakdown with Axion Like Particles
-
Alex Gomes Dias
(
Universidade Federal do ABC
)
Conecting the Inverse Seesaw Mechanism to a Symmetry Breakdown with Axion Like Particles
Alex Gomes Dias
(
Universidade Federal do ABC
)
18:00 - 18:20
Room: Aula Magna
We present a model in which the breakdown of a global U(1) symmetry, leading to a axion like particle, trigger the inverse seesaw mechanism. The mass scale parameters required in such a mechanism are generated through gravity induced nonrenormalizable operators and the vacuum expectation value of a scalar field hosting the axion like particle, which may be behind physical phenomena like the Universe transparency to ultra-energetic photons, the soft \gamma -ray excess from the Coma cluster, and the 3.5 keV line. Strong gravitational effects that destabilize the axion like particle and the inverse seesaw mechanism are shown to be suppressed by anomaly free discrete symmetries.
18:20
AMELIE: An Axion Modulation hELIoscope Experiment
-
Javier Galan
(
University of Zaragoza
)
AMELIE: An Axion Modulation hELIoscope Experiment
Javier Galan
(
University of Zaragoza
)
18:20 - 18:40
Room: Aula Magna
In this work, I will present an innovative idea to search for solar axions using a large volume low background TPC immersed in a magnetic field. This technique will be sensitive to axion masses above few meV in the theoretically favoured QCD-axion parameter space. The detector geometry will be such that will allow to monitor the Solar axion flux during full day. A stationary detector would produce a daily and annual modulation signal pattern given by the angle of the incident axion flux and the TPC magnetic field which is driven by earth rotation. Recent progress on large volume low background TPC's for rare event searches motivates the development of such helioscope technique. The principle of detection and prospects on the sensitivity of such experiment will be shown.
18:40
Solar Chamelons searches with the KWISP force sensor
-
Giovanni Cantatore
(
INFN Trieste
)
Solar Chamelons searches with the KWISP force sensor
Giovanni Cantatore
(
INFN Trieste
)
18:40 - 19:00
Room: Aula Magna
The KWISP opto-mechanical force sensor has been built and calibrated in the Trieste optics laboratory and is now under off-beam commissioning in CAST. It is designed to detect the pressure exerted by a flux of solar Chameleons on a thin (50 nm) silicon nitride micromembrane thanks to their direct coupling to matter. The membrane is placed inside a Fabry-Perot optical resonator excited at 1064 nm, and its displacements are monitored through the resonator characteristic frequencies. Displacements as little as 1e-15 m can be detected in 1 s, corresponding to a force sensitivity of < 1e-14 N. This sensitivity opens access to unexplored regions in the Chameleon parameter space, and may allow a first experimental glimpse at the nature of Dark Energy. Once installed on CAST, the KWISP force sensor will immediately exploit the flux focusing action of an X-Ray Telescope and the tracking capability to increase its sensitivity by a factor more than 100. We will present the preliminary measurements done in Trieste, the current status and the near and long term perspectives for further extending the physics reach in the Dark Energy sector.
Friday, 26 June 2015
09:00
ADMX-HF
-
Karl van Bibber
(
University of California Berkeley
)
ADMX-HF
Karl van Bibber
(
University of California Berkeley
)
09:00 - 09:35
Room: Aula Magna
09:35
Direct detection of dark matter with XENON
-
Ludwig Rauch
(
Max-Planck-Institut für Kernphysik
)
Direct detection of dark matter with XENON
Ludwig Rauch
(
Max-Planck-Institut für Kernphysik
)
09:35 - 10:00
Room: Aula Magna
The XENON100 experiment was designed to test the particle nature of dark matter by directly detecting their interactions with a target nuclei. The detector is a dual-phase time projection chamber, containing a total mass of 161kg liquid-xenon. It is located at the Laboratori Nazionali del Gran Sasso in Italy and optimized to search for Weakly Interacting Massive Particles (WIMPs). To this date, there is no conclusive evidence for a direct detection of dark matter. In this talk, the highlights of the science results derived by the XENON100 detector will be presented. In addition to the WIMP search results, bounds on galactic as well as solar axions will be presented. Finally, the construction status of the next generation detector XENON1T will be briefly reviewed and its scientific potential summarized.
10:00
The CAST-CAPP Experiment: Haloscope Axion Searches with the CAST Dipole Magnet.
-
Lino Miceli
(
IBS Center for Axion and Precision Physics
)
The CAST-CAPP Experiment: Haloscope Axion Searches with the CAST Dipole Magnet.
Lino Miceli
(
IBS Center for Axion and Precision Physics
)
10:00 - 10:25
Room: Aula Magna
The CAST-CAPP Experiment: Haloscope Axion Searches with the CAST Dipole Magnet. Lino Miceli IBS Center for Axion and Precision Physics Research (CAPP) Korea Advanced Institute of Science andTechnology Daejeon, Republic of Korea The CAST-CAPP experiment is a joint effort between the CERN Axion Solar Telescope (CAST) collaboration [1] and the Center for Axion and Precision Physics Research (CAPP). The CAPP, located at the Korea Advanced Institute of Science and Technology (Daejeon, South Korea), focuses on two key issues of contemporary physics: the nature of dark matter [DM], and the origin of the matter anti-matter asymmetry of our universe. The nature of DM is investigated through a comprehensive QCD-axion search program including this experiment. Tunable rectangular cavities will be inserted in the 43 mm twin-bore, 9T, CAST dipole magnet. This will be the first time in which the traditional haloscope technique [2] will be applied in rectangular, rather than cylindrical, geometry. The cavity operational frequency will be in the ~5 to 6 GHz range, corresponding to an axion mass of ~21 to 25 eV. The CAST-CAPP experiment sensitivity could reach into the QCD axion parameter space in this yet unexplored mass region. [1] CAST Collaboration, K. Zioutas et al., Phy. Rev. Lett. 94 (2005) 121301. [2] P. Sikivie, Phys. Rev. Lett. 51, 1415 (1983).
10:25
Primordial Chiral Gravitational Waves from the Axiverse
-
Ippei Obata
(
Department of Physics, Kyoto University
)
Primordial Chiral Gravitational Waves from the Axiverse
Ippei Obata
(
Department of Physics, Kyoto University
)
10:25 - 10:50
Room: Aula Magna
It is known that, the “axion”, the pseudo NG boson of a broken chiral sym- metry, is a favorable candidate for an inflaton; it preserves an inflaton’s potential against quantum loop corrections due to its shift symmetry. The presence of ax- ions in the early universe is strongly suggested by string theory. On the contrary, string theory suggests the presence of a plenitude of axions through a compactifi- cation in an extra-dimensional complex manifold. It is expected that these many axions with a wide mass range affect various cosmological phenomena, just like an inflationary universe. Under such a description, dubbed “axiverse”, we study the possibility of realizing an axionic inflation consistent with the observation of CMB polarization. We focus on the property of primordial gravitational waves derived from such an axionic inflation. String axions generally couple to Chern-Simons terms of gauge fields due to the anomaly cancellation, and remarkably, this interaction sources the tensor components of metric perturbations and can enhance one helic- ity mode of gravitational waves, producing primordial chiral gravitational waves. In this talk, we verify the possibility of detecting such an interesting signal from the axiverse in future experiments, without contradicting CMB observations. This presentation is based on the following our work (arXiv:1412.7620 [hep-ph]).
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula Magna
11:20
New effects of dark matter which are linear in the interaction strength
-
Benjamin Roberts
(
University of New South Wales
)
New effects of dark matter which are linear in the interaction strength
Benjamin Roberts
(
University of New South Wales
)
11:20 - 11:45
Room: Aula Magna
The boson dark matter particles produced after Big Bang may form a Bose condensate and/or topological defects. In contrast to traditional dark matter searches, effects produced by interaction of an ordinary matter with this condensate and defects may be first power in the underlying interaction strength, which is extremely small, rather than the second power or higher. We discuss new effects and schemes for the direct detection of dark matter, including axions, axion-like pseudoscalar particles (ALPs) and scalar particles, as well as topological defects. Specific effects produced by the particle condensates include: space-time variation of the fundamental constants (fine structure constant alpha, particle masses, etc) including both slow variation (on the cosmological scale) and fast oscillations, oscillating atomic electric dipole moments, precession of electron and nuclear spins about the direction of Earth’s motion through an axion/ALP condensate (the axion wind effect), axion-mediated spin-gravity couplings, and oscillating variations in phase shifts produced in laser/maser interferometers (such as LIGO, Virgo, GEO600 and TAMA300) by a scalar particle condensate. Topological defects (which may also be a part of dark matter) may produce changes in pulsar rotational frequencies (which may have been observed already in pulsar glitches), non-gravitational lensing of cosmic radiation and the time-delay of pulsar signals. Topological defects may also produce transient and correlated observable effects in a global network of atomic clocks, magnetometers (spin precession effects and transient electric dipole moments) and laser/maser interferometers, as well as alter the rate of Earth rotation. The proposed detection methods offer sensitive probes into important, unconstrained regions of dark matter parameter spaces. References: [1] Y. V. Stadnik and V. V. Flambaum. Phys. Rev. D 89, 043522 (2014). [2] B. M. Roberts, Y. V. Stadnik, V. A. Dzuba, V. V. Flambaum, N. Leefer and D. Budker. Phys. Rev. Lett. 113, 081601 (2014). [3] Y. V. Stadnik and V. V. Flambaum. Phys. Rev. Lett. 113, 151301 (2014). [4] B. M. Roberts, Y. V. Stadnik, V. A. Dzuba, V. V. Flambaum, N. Leefer and D. Budker. Phys. Rev. D 90, 096005 (2014). [5] M. Pospelov, S. Pustelny, M. P. Ledbetter, D. F. Jackson Kimball, W. Gawlik, and D. Budker. Phys. Rev. Lett. 110, 021803 (2013). [6] A. Derevianko and M. Pospelov. Nature Physics 10, 933 (2014). [7] Y. V. Stadnik and V. V. Flambaum. arXiv:1412.7801 [8] P.W. Graham, S. Rajendran. Phys. Rev. D84,055013 (2011); D88,035023 (2013).
11:45
Axion miniclusters
-
Igor Tkachev
(
INR RAS
)
Axion miniclusters
Igor Tkachev
(
INR RAS
)
11:45 - 12:10
Room: Aula Magna
12:10
Search for axion-like particle signatures in the gamma-ray spectrum of NGC 1275
-
Manuel Meyer
(
Stockholm University
)
Search for axion-like particle signatures in the gamma-ray spectrum of NGC 1275
Manuel Meyer
(
Stockholm University
)
12:10 - 12:35
Room: Aula Magna
Axion-like particles (ALPs) occur in a variety of extensions of the Standard Model and are a viable candidate for a constituent of dark matter. ALPs are predicted to couple to photons in external magnetic fields and thus could leave an imprint on gamma-ray spectra. Around the critical energy for photon-ALP conversions, oscillatory features together with a decrease of the photon flux are expected. Especially sources located in galaxy clusters are well suited for searches of these spectral features as galaxy clusters are known to harbor magnetic fields over large spatial extensions. One particular example is the radio galaxy NGC1275 at the center of the Perseus cluster: the value of the central cluster magnetic field is high (of the order of 10μG) and the source is bright in the energy range covered with the Large Area Telescope (LAT) on board the Fermi satellite. Here, we present the expected sensitivity of the Fermi LAT to the detection of the spectral features. The analysis makes use of the latest instrumental response functions and a detailed modelling of the turbulent cluster magnetic field. For ALP masses between 1 and 10 neV, the Fermi-LAT measurements are expected to be more sensitive than future laboratory searches and might be able to probe optimistic models of ALP dark matter.
12:35
First results of the CASCADE light shining through a wall experiment
-
Nathan Woollett
(
Lancaster University and The Cockcroft Institute
)
First results of the CASCADE light shining through a wall experiment
Nathan Woollett
(
Lancaster University and The Cockcroft Institute
)
12:35 - 13:00
Room: Aula Magna
Light shining through a wall experiments can be used to make measurements of photon-WISP couplings. The first stage of the CASCADE experiment at the Cockcroft Institute of Accelerator Science and Technology is intended to be a proof-of-principle experiment utilising standard microwave technologies to make a modular, cryogenic HSP detector to take advantage of future high-power superconducting cavity tests. In this presentation I will be presenting the first results of the CASCADE LSW experiment showing a best in mass range exclusion.
13:00
Search for a leptophibic B-boson via eta decay at Jlab
-
Liping Gan
(
University of North Carolina Wilmington
)
Search for a leptophibic B-boson via eta decay at Jlab
Liping Gan
(
University of North Carolina Wilmington
)
13:00 - 13:25
Room: Aula Magna
A leptophibic B-boson couples predominantly to quarks and arises from a new U(1) baryon number gauge symmetry [1]. Its leading decay is B→π^0+γ for the mass range of 140-620 MeV [2]. This offers a great experimental opportunity to search for such weakly-coupled gauge boson in the sub-GeV mass range through eta doubly-radiative decay η→Bγ→π^0γγ. Jlab Eta Factory (JEF) experiment [3] has been recently developed to search for B through this decay channel, with sensitivity to the baryonic fine structure constant as low as 10E−7, indirectly constraining the existence of anomaly cancelling fermions at the TeV-scale. Proposed experiment to search for B in three-photon final states (B→π^0γ→3γ) is complementary to a world wide effort searching for a dark photon A' at the high-intensity frontiers. Reference: [1] B. Batell et. al., Phys. ReV., D90, 115014 (2014). [2] S. Tulin, Phys. Rev., D89, 14008 (2014). [3] L. Gan et. al., https://www.jlab.org/exp_prog/proposals/14/PR12-14-004.pdf.
14:00
Patras 2016 announcement
-
Dominika Konikowska
(
IBS/CAPP
)
Patras 2016 announcement
Dominika Konikowska
(
IBS/CAPP
)
14:00 - 14:20
Room: Aula Magna