12th AxionWIMP conference (Patras workshop)

20 Jun 2016, 08:00 → 24 Jun 2016, 18:30 Asia/Seoul

The Suites Hotel (Jeju Island, South Korea)

The 12th Patras Workshop on Axions, WIMPs and WISPs will be held at Jeju Island (South Korea) from June 20th to 24th, 2016. This volcanic island is located 130 km from the southern coast of Korea, and is listed amongst the New 7 Wonders of Nature. This workshop continues a rich and successful series, reviewing recent theoretical advances, laboratory experiments, as well as astrophysical and cosmological results in the fields of axions, WIMPs and WISPs.
Participation by young scientists is encouraged, as this series started as Training Workshops at CERN. A poster session is scheduled, and an award is foreseen to recognize the best poster contribution.
A registration fee of 500,000 KRW (250,000 KRW for students) covers breakfasts at the hotel, lunches, coffee breaks, conference dinner and social/cultural events. Late registration (after April 25th) entails the registration fee increase to 600,000 KRW (300,000 KRW for students).
More details on the workshop are given on the conference webpage:
http://axion-wimp2016.desy.de/

Misc RegistrantsList.pdf

Paper Patras_Agenda-2016_0529.pdf

Monday, 20 June

08:30 → 09:00 Conference registration

09:00 → 09:15 Welcome and introduction

Slides 01.YkS_Patras_Welcome_2016_0620.ppt

09:15 → 09:45 CP-conservation in QCD and why only axions work (tentativ)

(tbd)

Speaker: Prof. Jihn E. Kim (Kyung Hee University, Seoul)

Slides 02.Jeju16.pdf

09:45 → 10:05 Status of KIMS-NaI Experiment

It is widely known that a large component of the universe's mass is in the form of dark matter and dark energy. There are several candidates for dark matter and WIMPs (Weakly Interacting Massive Particles) are considered to be one of the most probable ones. Until now, only the DAMA/LIBRA experiment, with NaI(Tl) crystals, has shown a statistically compelling positive result, which is a WIMP-like annual modulation, but this still under considerable debate. The KIMS-NaI group is preparing to test the DAMA/LIBRA annual modulation signal unambiguously, with an array of low-background NaI(Tl) crystals at the Yang Yang Underground laboratory. For this, we studied more than ten NaI(Tl) crystals as part of an R&D program aimed at reducing internal backgrounds to achieve better quality crystals than those used by DAMA/LIBRA. The first phase of experiment with a ~100kg array of NaI(Tl) crystals will be ready soon. In this talk, we will present the results of the NaI(Tl) crystal R&D program, the current status of the KIMS-NaI experiment, and future prospects.

Speaker: Dr Jungsic Park (Institute for Basic Science)

Slides PATRAS_2016_KIMS-NaI_jspark_ver1.pdf

10:05 → 10:30 Latest results with the KWISP force sensor at CAST

The KWISP opto-mechanical force sensor has started searching for solar chameleons through their direct coupling to matter. Its sensing element, a 100 nm thick Si3N4 membrane, was mounted in the focal plane of the CAST X-ray telescope, which focuses also chameleons, and several solar runs were completed using the key sun-tracking capability of the CAST magnet. KWISP is designed to detect, with optical techniques, extremely tiny membrane displacements due to the force exerted by chamelons recflecting off it. The measurement is made possible by a specially devised chamelon beam chopper providing an amplitude modulation, which is instrumental for detection. The KWISP particle sensing technique is presently unique in astroparticle physics. We will present the KWISP setup, discuss its status and results, and focus on upcoming developments.

Speaker: Prof. Cantatore Giovanni (Università and INFN, Trieste, Italy)

Slides cantatore_Patras2016.pdf

10:30 → 11:00 Search for Hidden Particles with SHiP

The SHiP (Search for Hidden Particles) is a newly proposed experiment at the CERN SPS in order to explore the domain of hidden particles with mass from sub-GeV up to O(10) GeV. It is designed to search in particular for very weakly interacting long lived particles with super-weak coupling down to 10^-10, such as Heavy Neutral Leptons (HNL), new scalar, fermionic and vector particles including dark matter particles. These particles would be produced in a proton beam dump at high intensity 400 GeV from decay of charm or beauty particles. The main experimental signature involves two charged decay tracks of HNL. The SHiP detector (total length is about 150m) consists of long evacuated decay volumes, which is followed by magnetic spectrometer, a calorimeter and muon detectors in order to allow full reconstruction and particle identification. Moreover, the facility is ideally suited to study the interactions of tau neutrinos. For this purpose, the emulsion target surrounded by a magnetic field is located upstream of the decay volumes. About 3000 tau neutrinos are expected to be observed with an integrated 2x10^20 protons on target. In addition, anti-tau neutrinos can be observed for the first time. In this talk, we will present the current status and long term schedule of the experiment.

Speaker: Prof. Chun Sil Yoon (Gyeongsang National University, Jinju, Korea)

Slides patras2016_yoon.pdf

11:00 → 11:30 Coffee break

11:30 → 11:50 Launching Axion Experiment at CAPP/IBS in Korea

The main research focus of the Center for Axion and Precision Physics Research (CAPP) at IBS is to establish a state-of-the-art axion experiment in Korea and to search for relic axion particles converting to microwave photons in a resonant cavity submerged in a strong magnetic field. The initial stage of building our axion experiment, CULTASK (CAPP Ultra Low Temperature Axion Search in Korea) is completed at KAIST (Korea Advanced Institute for Science and Technology) Munji Campus with successful installation of two new dilution refrigerators (one with 8T superconducting magnet) which could lower the temperature of cavities to less than 50 mK. A resonant cavity (10 cm OD) and the support structure were fabricated and installed with the frequency tuning system employing a sapphire rod driven by a piezoelectric actuator. The RF measurements were also performed for evaluating and improving noise figures using cryogenic HEMT amplifiers. I will discuss the status and progress of CULTASK, soon to be complete with a DAQ and monitoring system, and future plans. I will also present the recent results from the development of high Q-factor, ultra pure Cu and Al cavities under high magnetic fields, utilizing the two refrigerators.

Speaker: Dr Woohyun Chung (CAPP/IBS)

Slides Patras_launchingAxion.pdf

11:50 → 12:15 The local dark matter distribution from hydrodynamic simulations

Our lack of knowledge of the details of the dark matter distribution in the Solar neighborhood introduces significant uncertainty in the interpretation of dark matter direct detection data. Dark matter only simulations of galaxy formation predict local velocity distributions which deviate substantially from a Maxwellian. I will discuss the local dark matter density and velocity distribution of simulated Milky Way analogues obtained from the high resolution EAGLE and APOSTLE hydrodynamic simulations which include baryons. To make reliable predictions for direct detection searches, we identify simulated haloes which satisfy the Milky Way observational constraints. Using the dark matter distribution obtained for the selected Milky Way analogues, I will present an analysis of direct detection data, and show how the allowed regions and exclusion limits set by direct detection experiments in the dark matter mass and spin-independent cross section plane shift with respect to the Standard Halo Model.

Speaker: Nassim Bozorgnia (GRAPPA, University of Amsterdam)

Slides Bozorgnia-Patras.pdf

12:15 → 12:35 Dark Energy at the LHC

I discuss the opportunities and limitations of LHC searches for dark energy using effective field theory techniques, predominantly focusing on mono-jet and top final states. Since these searches are based on high momentum transfer and relativistic final states, I will also discuss the range of validity that dark energy interpretations of such signatures face.

Speaker: Dr Christoph Englert (University of Glasgow)

Slides 2016_Jeju_englert.pdf

12:35 → 13:00 Single Microwave Photon Detectors for High Frequency Axion Detection

High quantum efficiency, qubit-based single microwave photon detectors are being developed for the Axion Dark Matter eXperiment (ADMX). This cross-disciplinary research aims to transfer the already mature qubit readout technology used in quantum computing and bring it to bear on particle physics applications. Because dark noise from thermal photons is exponentially suppressed in low temperature operation, the effective noise power of these photon counting detectors can be orders of magnitude below that of the quantum-limited linear amplifiers presently used in axion searches. The resulting improvement in the signal-to-noise ratio will enable future searches for dark matter axions at higher mass.

Speaker: Dr Chou Aaron (FNAL)

Slides achou_patras2016final.pdf

13:00 → 14:00 Lunch

14:00 → 14:30 SM*A*S*H - Standard Model * Axion * See-saw * Hidden scalar inflation

A minimal extension of the Standard Model (SM) is presented that provides a consistent picture of particle physics and cosmology below the Planck scale accounting for inflation, baryogenesis, dark matter, neutrino masses and solving the strong CP problem. We add to the SM three right-handed SM singlet neutrinos, a new vector-like color triplet fermion and a complex hidden scalar whose vacuum expectation value at ∼ 10^11 GeV breaks lepton number and the Peccei-Quinn symmetry simultaneously. At low energies, the model reduces to the SM, augmented by see-saw-generated neutrino masses and mixing, plus the axion, which accounts for the dark matter. Five fundamental problems of particle physics and cosmology are solved at one stroke in this unified Standard Model Axion See-saw Hidden scalar inflation (SM*A*S*H) model.

Speaker: Dr Andreas Ringwald (DESY)

Slides patras_2016_ar.pdf

14:30 → 14:50 Detecting very low mass Dark Matter particles with NEWS-SNO

The existence of Dark Matter in our Universe is nowadays well established, however, its exact nature still remains unknown. The goal of the NEWS-SNO (New Experiments with Spheres in SNOLAB) project is to search for particle candidates in mass regions not yet accessible by existing experiments. The planned NEWS-SNO detector consists of a spherical TPC (time-projection-chamber) out of ultrapure copper ,filled with up to 10bar of CH4 and He gas mixtures which is read out with one central sensor set at high voltage. Thanks to the very light nuclear mass of the employed targets as well as the very low energy threshold, the detection of spin-independent and spin-dependent interacting WIMPS down to masses of 0.1 GeV/c2 is aimed at. This mass range for Dark Matter particles is motivated in a number of models based on dark sector forces and, e.g., millicharged models. Changing the nature and/or mix of gas, the pressure, the HV, the sensor are knobs that could be used to check a possible dark m atter like signal. An overview and status of the planned experiment at SNOLAB and results of the prototype detector SEDINE operated with Neon gas in the Laboratoire Souterrain de Modane underground laboratory in France will be given.

Speaker: Dr Gilles Gerbier (Queen's University, Kingston, Canada)

Slides NEWS_Patras_june16_GG_f.pdf

14:50 → 15:10 Status and Recent Results from the PandaX Experiment

The PandaX (Particle AND Astrophysical Xenon) project is a staged xenon-based underground experiment at the China Jin-Ping Underground Laboratory. The first phase experiment, PandaX-I, a 120 kg dark matter detector using a dual phase xenon time projection chamber (TPC) technology was completed in 2014 with a 54 x 80.1 kg-day exposure; no dark matter candidate was found. Recently, the commissioning run of the second phase of the experiment, PandaX-II, was completed, with a 306 × 19.1 kg-day exposure data released. The physics run of PandaX-II is expected to start in 2016. In this talk, I will report the status of the PandaX experiment, and then present the results from recent dark matter searches.

Speaker: Dr Mengjiao Xiao Xiao (Shanghai Jiao Tong University)

Slides 03.PandaX_Patras_Mengjiao.pdf

15:10 → 15:30 Nonperturbative Dynamics in Dark Matter Freezeout

I discuss the cosmological impact of dark matter bound state formation in the early universe in the context of complete simplified models of dark matter interactions. In particular, I show that the effects of relativity on the nature and behavior of these bound states are important to correctly describe the physics in cases of interest. I continue on to discuss the implications of these interactions for the parameter space of well-motivated models of dark matter, especially in the context of unitarity considerations which lead to upper bounds on the mass of thermal dark matter.

Speaker: Dr William Shepherd (Niels Bohr International Academy)

Slides Unitarity_Patras.pdf

15:30 → 15:50 Muon g-2 and pEDM experiments at CAPP/IBS

The precise measurement of the muon anomalous magnetic moment is very important to check the possibilities of physics beyond the Standard Model. The new muon g-2 experiment at FNAL aims to measure the muon anomalous magnetic moment with four times better precision than previous experiment at BNL and plans to start the experiment at 2017. The Storage Ring proton EDM experiment has a New Physics sensitivity in the range of 10^3 - 10^4 TeV. Using techniques similar to the classical muon g-2 experiment we can probe the proton EDM with high sensitivity. This is due to high intensity polarized proton beams readily available as well as the long spin coherence lifetime possible in all-electric rings. There are a few important technical issues for both experiments that we are addressing. The principle, experiment techniques and CAPP/IBS contributions for both experiments will be presented.

Speaker: Dr Young-Im Kim (Institute for Basic Science (IBS), Daejeon)

Slides 20160620_PatraWorkshop_youngim.pdf

15:50 → 16:10 The CRESST experiment: Current status and future developement

Located in the Gran Sasso underground laboratory, the CRESST ex- periment aims for the direct detection of dark matter by using cryogenic calorimeters to detect dark matter induced nuclear scattering processes in scintillating CaWO4 crystals. The identification and rejection of back- grounds is crucial for rare event searches like CRESST. Therefore, a two channel readout detector is implemented that allows to distinguish be- tween different particle interactions by the ratio of energy deposited di- rectly in the CaWO4, measured as heat, and the amount of scintillation light being simultaneously produced. In the last physics run, CRESST-II (Phase 2) was able to explore new regions in the DM parameter space and to set the leading limit for dark matter masses below ≈1.7 GeV/c2 . In the future (CRESST-III (Phase 1)), the CRESST experiment will focus on the low-mass dark matter region. Based on established detector techniques, a new detector module was developed which is optimized for very low detection thresholds (<100 eV). Featuring a 10 times smaller CaWO4 crystal, the heat channel of the detectors is significantly improved compared to older designs and opens access to new regions in the dark matter parameter space. Currently, this new generation of detectors is installed underground and ready for data taking. The talk will give an overview of the latest results and of the current status of the detector R&D.

Speaker: Mr Marc Wuestrich (Max-Planck-Institute f. Physics)

Slides Patras_Wuestrich_CRESST.pdf

16:10 → 16:40 Coffee break

16:40 → 17:15 WIMP direct detection: toward a minimal set of assumptions

The difficulty of finding a direct signal from weakly-interacting particle dark matter has lead to phenomenological models that make a minimal number of assumptions on the particle physics and astrophysics models. In this talk, I will present the ideas behind this approach, the most important results, and the current directions of research.

Speaker: Prof. Gondolo Paolo (University of Utah)

Slides 2016d-Jeju.pdf

17:15 → 17:50 GW150914: a black hole binary merger discovered by gravitational-wave observation

Exploring the universe with gravitational waves (GWs) was only a theoretical expectation for the last 100 years after Einstein's theory of general relativity. In September 2015, the US-based Laser Interferometer Gravitational-wave Observatory (LIGO) first detected GWs emitted from the collision of two stellar-mass black holes at cosmological distance (1.3 billion light years) from Earth. The event, labeled as GW150914, confirms the existence of black-hole binary mergers, and further, opens a new field of GW astronomy. I will give a brief overview on the detection of GW150914 and discuss prospects of GW astronomy. In addition to the information about sources we obtain via GWs, coordinated follow-up observations using electromagnetic waves and neutrinos will be useful to better understand some of the universe’s most energetic phenomena.

Speaker: Dr Chunglee Kim (Seoul National University)

Slides 08.patras2016_CKim.pdf

17:50 → 18:10 QUAX and AXIOMA: new experimental methods in axion detection

We present two different experimental schemes in the field of axion detection that are under investigation within the context of the research call "What Next" of INFN. AXIOMA is a project based on laser-spectroscopy techniques, in which the incident particle contributes to the excitation of an atomic or molecular low-lying energy level and is detected through a fluorescence signal from a higher energy level. QUAX exploits the interaction of the cosmological axion with the spin of fermions (electrons or nucleons). In recent theoretical works the effect of the “axion wind” on a magnetized material is described as an effective oscillating microwave field with frequency determined by the axion mass and amplitude related to the symmetry breaking scale. An axion detector can then be developed through a magnetized sample whose Larmor frequency is tuned to the axion mass by means of an external polarizing static field (e.g. 0.6 T for 17GHz, corresponding to a 70μeV axion mass). The interaction with the axion effective field drives the total magnetization of the sample, whose oscillations can be possibly detected through the LOngitudinal Detection technique (LOD), even though a bolometric approach is also being considered.

Speaker: Dr Caterina Braggio (University of Padova and INFN)

Slides presentation1.pdf

18:10 → 18:30 Round table discussion

Tuesday, 21 June

08:40 → 09:10 Conference registration

09:10 → 09:45 Status of the Cosmic Axion Spin Precession Experiment (CASPEr)

xions and axion-like particles (ALPs) are well-motivated dark matter candidates, but are challenging to detect experimentally. Current experiments such as ADMX (the Axion Dark Matter eXperiment) are based on the coupling of ALPs to electromagnetic fields, and practical experimental considerations (e.g. constraints on microwave cavity size) typically limit such searches to axion/ALP masses greater than about $10^{-6}$~eV. The Cosmic Axion Spin Precession Experiment (CASPEr) tackles the problem from a new direction by using nuclear magnetic resonance (NMR) techniques to search for nuclear spin precession caused by background axion/ALP dark matter. CASPEr is naturally divided into two main efforts, based on the two couplings between axions and nuclear spins: CASPEr-Wind searches for the ``axion wind'' effect -- the direct coupling of nuclear spins to the relative momentum of the ALP field, and CASPEr-Electric searches for the oscillating nuclear electric dipole moment caused by the QCD axion. Under appropriate experimental conditions, both of these couplings behave analogously to RF magnetic fields, in that they can induce measurable spin precession if the frequency of oscillation of the axion field (corresponding to the axion mass) is equal to the nuclear Larmor frequency. By sweeping the applied magnetic field from $\sim$10$^{-5}$ to 14.1~T, CASPEr will be able to probe the ALP parameter space for masses between $\sim$10$^{-12}$ and $6.9\times 10^{-7}$~eV. Current efforts in the technical design and construction of CASPEr will be discussed.

Speaker: Dr John Blanchard (Helmholtz-Institut Mainz, Germany)

Slides Blanchard_CASPEr-Patras2016_for_upload.pdf

09:45 → 10:05 LUX

LUX is a 370 kg two-phase xenon TPC detector which has been operating underground at Sanford Lab (USA) since 2012. We report on several notable results from new analysis of the WIMP dark matter search data, and precision calibrations.

Speaker: Dr Simon Fiorucci (Department of Physics Brown University, Providence, US)

Slides 20160621_Fiorucci_PATRAS_LUX.pdf

10:05 → 10:25 GERDA - Phase I results and news from the Phase II upgrade

The Gerda experiment, located at Laboratori Nazionali del Gran Sasso (LNGS) of INFN, conducts neutrinoless double beta decay (0nbb) search in the candidate isotope 76Ge. In a first experimental phase a lower limit of the half-life, 2.1x10^25 yr (at 90% CL), was determined. This result strongly disfavors the famous claim from 2004. The half-life of the ordinary double beta decay (2nbb) of 76Ge was re-measured using Phase I data, achieving a significant reduction of uncertainties. Furthermore, the possibility of 0nbb decay with Majoron emission was evaluated for different spectral indices. Recently, the decay of 76Ge into excited states of 76Se was investigated. Lower half-life limits for three transitions have been published which are about two orders of magnitude larger than the previously reported values. Several models could be excluded by this analysis. Gerda has just entered the Phase II data taking. The experimental setup has been modified in order to meet the competitive goal to reach half-lives in the range of 10^26 yr. A new lock-system has been installed which can hold up to seven detector strings. This gives the possibility to deploy new detectors, augmenting the experimental active mass. To supplement Gerda Phase II, detectors of Broad Energy Germanium (BEGe) type were produced in 2012 and 2013, which have excellent Pulse Shape Discrimination (PSD) properties. In contrast to Phase I, all detectors are now contacted by wire bonds and the detector holders have been improved. Another major development is the implementation of a new veto system utilizing Argon scintillation light in order to identify background from radioactive decays and Compton events in the vicinity of the detectors in the Gerda liquid Argon (LAr). Fist light from the LAr veto was measured and very promising results have been obtained. Background rejection by PSD and the new veto system are a key feature in Gerda Phase II in order to achieve the design goal of a background index of 10^−3 cts/(keV kg yr). In this talk, results from Gerda Phase I will be discussed and news from the Gerda Phase II upgrade will be presented.

Speaker: Dr Katharina von Sturm (Università delgi Studi di Padova)

Slides 201606_KvS_Gerda_Patras.pdf

10:25 → 10:45 Preliminary Study for a New Axion Dark-Matter Haloscope

A collaboration between CAPP/IBS, KAIST in Korea and teams from CNRS/Université Grenoble Alpes, in France is studying the possibility of developing a new haloscope for Axion dark-matter search. The superconducting coil under construction at LNCMI-Grenoble will provide a magnetic field of 9 T in a cylinder of 800 mm diameter and 1 meter high. This large bore superconducting magnet can host various types of microwave cavity detectors for the Axion to photon resonant conversion via the inverse Primakoff effect following the Sikivie’s detection scheme. These cavities, possibly superconducting, are presently under study at CAPP/IBS and will have a high quality factor Q in the range 10^5-10^7. Low-noise microwave amplification of the signal will be ensured by a DC superconducting quantum interference device (SQUID) or Josephson Parametric Amplifiers (JPA) cooled-down to 50 mK by a 3He/4He dilution refrigerator. This new haloscope will be designed to probe QCD dark-matter Axions in the mass range of 1-100 micro-eV with diphoton coupling constant reaching the theoretical prediction of the Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) model.

Speaker: Dr Pierre Pugnat (CNRS/LNCMI-Grenoble)

Slides Preliminary_Study_for_a_New_Axion_Dark-Matter_Haloscope.pdf

10:45 → 11:10 SUSY DM predictions for Direct Detection Experiments, the LHC and the ILC

We perform a fit of various SUSY models (with a WIMP DM candidate) to experimental data from LHC searches, astrophysical data, low-energy and flavor observables. Based on this analysis we give predictions for the propects of Direct Detection experiments, ongoing LHC searches and future ILC searches. We stress the complementarity of the various searches to determine the nature of DM.

Speaker: Dr Miriam Lucio Martínez (Santiago de Compostela, Spain)

Slides Lucio_Patras.pdf

11:10 → 11:40 Coffee break

11:40 → 12:05 Status of XENON experiment

Cosmological observations provide strong evidence for an invisible and dominant mass component. If the dark matter is made of Weakly Interacting Massive Particles (WIMPs), it can be directly detected via elastic scattering from nuclei in ultra-low background, deep-underground detectors. Among various direct dark matter search experiments, the experiments utilizing liquid-gas dual phase xenon Time Projection Chamber (TPC) are leading the field. The XENON1T experiment is the ton-scale liquid xenon detector at the National Laboratory of Gran Sasso, Italy. The design characteristics, the status, and the scientific reach of the XENON1T will be covered.

Speaker: Junji Naganoma (Rice University)

Slides Patras2016_XENON_junji.pdf

12:05 → 12:25 Dark Matter Search with DARWIN

DARWIN (DARk matter WImp search with Noble liquids) is a future multi-ton scale detector for the direct detection of Weakly Interacting Massive Particles (WIMPs). The detector will be based on a xenon dual-phase time projection chamber (TPC) with simultaneous charge and light readout. The goal is to build the ultimate detector for WIMP masses above ~5GeV/c^2, whose sensitivity will only be limited by the irreducible neutrino background. This talk will focus on the physics reach and R&D activities related to DARWIN.

Speaker: Dr Moritz von Sivers (University of Bern)

Slides PATRAS16_sivers.pdf

12:25 → 12:50 MoEDAL – A New Experiment at the LHC's Doscovery Frontier

MoEDAL is a pioneering experiment designed to search for highly ionizing messengers of new physics such as magnetic monopoles or massive (pseudo-)stable chargedparticles. Its ground-breaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; what is the nature of dark matter; and, how did the big-bang develop at the earliest times. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field.The physics reach of the existing MoEDAL detector is discussed along with the physics possibilities of SLAC type millicharged particle “beam dump” type MoEDAL sub-detector. I will also briefly describe MoEDAL’s innovative and unconventional detector methodologies tuned to the prospect of discovery physics. Finally, the first results will be presented.

Speaker: Prof. James Pinfold (University of Alberta, Edmonton, Canada)

Slides Patras-Korea_-2016-Pinfold.pptx

12:50 → 13:15 The LUX-ZEPLIN Dark Matter Experiment

The LUX-ZEPLIN (LZ) is an experiment to search for weakly-interacting dark matter particles (WIMPs) with unprecedented sensitivity. It will probe spin-independent WIMP nucleon cross sections down to 2×10−48 cm2 at 50 GeV/c2 within 3 years of operation, covering a wide range of theoretically-motivated dark matter candidates. The core of the LZ experiment is a two-phase xenon (Xe) time projection chamber (TPC) containing 7 active tonnes of liquid Xe (LXe). The central cryostat vessels that contain the TPC will be surrounded by a liquid organic scintillator outer detector and mounted inside the water tank that has been used by LUX, at Sanford Underground Research Facility (SURF), SD, USA. An overview of the design of LZ will be presented, along with its expected backgrounds and projected sensitivity.

Speaker: Prof. M. Isabel Lopes (LIP-Coimbra, Department of Physics, University of Coimbra, Rua Larga, 3004-516 Coimbra, Portugal)

Slides LZ_IsabelLopes_PATRAS2016.pdf

13:15 → 14:15 Lunch

14:15 → 14:35 An abundance of relaxions?

There has been significant interest in using a coupling between the Higgs and the axion to resolve the electroweak hierarchy problem. This relaxion idea while intriguing also may present a problem for the QCD axion's original intention, to solve the strong CP problem. In this model, the axion may also be eliminated as a resolution to the dark matter problem. In this talk I will discuss ways this problem might be solved, implications it may have for the dark matter problem as well as studies of inflation.

Speaker: Dr Chanda Prescod-Weinstein (University of Washington)

Slides Prescod-Weinstein_Patras_2016_Final.pdf

14:35 → 14:55 Axion haloscopes with toroidal geometry at CAPP/IBS

The present state of the art axion haloscope employs a cylindrical resonant cavity in a solenoidal field. We, the Center for Axion and Precision Physics research (CAPP) of the Institute for Basic Science (IBS) in Korea, are also pursuing halo axion discovery using this cylindrical geometry. The presence of end caps of cavities increases challenges as we explore higher frequency regions for the axion at above 2 GHz. To overcome these challenges we exploit a toroidal design of cavity and magnetic field. A toroidal geometry offers several advantages, two of which are a larger volume for a given space and greatly reduced fringe fields which interfere with our preamps, in particular the planned quantum based versions. We introduce to a concept of toroidal axion haloscopes and present ongoing research activities and plans at CAPP/IBS.

Speaker: Byeong Rok Ko (CAPP/IBS)

Slides 02.Patras_toroid_CAPP_BRKo_sub.pdf DM_search_with_new_magnets.pptx

14:55 → 15:15 Searches for Axion-Like Particles with NGC1275

Axion-like particles (ALPs) can induce localised O(10%) oscillatory modulations in the spectra of photon sources passing through astrophysical magnetic fields. Ultra-deep Chandra observations of the Perseus cluster contain over 500,000 counts from the central NGC1275 AGN and represent a dataset of extraordinary quality for ALP searches. We use these to search for X-ray spectral irregularities from the AGN. The absence of irregularities at the O(30%) level allows us to place leading constraints on the ALP-photon mixing parameter g_{aγγ}≲1.5−5.4×10^{−12}GeV−1 m_a≲10^{−12}eV, depending on assumptions on the magnetic field realisation along the line of sight. At O(10%) level two modulations are present at high statistical significance, an excess in the 2-2.2 keV region and a deficit at 3.4-3.5 keV. We are unable to account for these through conventional instrumental or astrophysical processes and, interpreted as a signal, they would correspond to an ALP-photon coupling in the range g_{aγγ}∼1−5×10^{−12}GeV.

Speaker: Dr Sven Krippendorf (University of Oxford)

Slides patras2016-SvenKrippendorf.pdf

15:15 → 15:35 Axion search with the CDEX-1 experiment

We present the search results from the China Dark Matter Experiment (CDEX) deploying a 991 g p-type point contact germanium detector at the China Jinping Underground Laboratory (CJPL), which has about 2400 m of rock overburdened. Using a total exposure of up to 365 kg.d, we search for axion-induced electron recoils down to 475 eV from the solar axions: Fe-57 nuclear magnetic transition and Compton, bremsstrahlung and axio-RD processes, as well as the galactic axion. The constrains of the coupling to electrons g_{Ae} from those processes are reported.

Speaker: Dr Shukui Liu (Tsinghua unviersity)

Slides 04.20160615_Tsinghua_University_Lsk_12thPatras.pdf

15:35 → 15:55 New limits on heavy ALPs: an analysis of SN 1987A, again

We determine limits from SN 1987A on massive axion-like particles with masses in the keV-GeV range and that couple exclusively to two photons. The signal we use to determine these limits arises from the decay of the heavy particles on their way to Earth resulting in observable gamma-rays. We discuss the non-trivial time and angular distributions of such a signal. Looking into the future we also estimate the possible improvements if the red supergiant Betelgeuse explodes in a supernovae event.

Speaker: Mr Pedro Cavalcanti Malta (Brazilian Centre for Research in Physics (CBPF) and Institute for Theoretical Physics (ITP - U. Heidelberg))

Slides Presentation_PATRAS.pdf

15:55 → 16:15 Gamma rays as probes of axions and axionlike particles

(The abstracts still needs to be approved by the FERMI collaboration)

Speaker: Dr Manuel Meyer (Oskar Klein Centre, Stockholm University)

Slides mmeyer_gamma-rays_ALPs.pdf

16:15 → 16:45 Coffee break

16:45 → 17:05 Dish Antenna Searches for WISPy Dark Matter: Directional Resolution and Limitations for Small Masses

Hidden photon and axion-like dark matter may be detected using spherical reflective surfaces such as in dish antenna setups converting some of the dark matter particles into photons and concentrating them on a detector. These setups may be used to perform directional searches measuring the dark matter momentum distribution. We present a calculation of the photon distribution one expects to detect with such an antenna in ray approximation and discuss implications on the sensitivity of discovery experiments and on the directional resolution. Furthermore we consider the regime $m_{DM} \lesssim (R_{sp}\,v_{DM})^{-1}$ where the ray approximation does not hold anymore due to photon wavelengths exceeding the expected distribution widths obtained in the ray approximation. We discuss how this affects the expected distributions and experimental implications.

Speaker: Mr Stefan Knirck (Institute for Theoretical Physics, University Heidelberg, Germany)

Slides PATRAS2016_DishAntennaResolution_StefanKnirck.pdf

17:05 → 17:30 DarkSide WIMP Search with Underground Argon

DarkSide-50 is a direct WIMP detection experiment at Gran Sasso underground laboratory in Italy based on a 50 kg dual-phase argon Time Projection Chamber with liquid argon from underground sources. DarkSide-50 aims to perform background-free WIMP searches with active vetos of a 30 tonne liquid scintillator neutron veto and a 1 k tonne water Cherenkov muon veto. DarkSide-50 has been taking data with underground Ar, which is significantly depleted in radioactive 39Ar, and measured its depletion factor. The result of WIMP searches with 70 live-days of underground argon data will be presented. Also, the recent study of the liquid scintillator veto’s performance and the future plan will be discussed.

Speaker: Masayuki Wada (Princeton University)

Slides M_Wada_Patras_Jun2016.pdf

17:30 → 17:55 Layered dielectric haloscopes: a new way to detect axion dark matter

Axions and axion-like particles are among the best-motivated candidates for dark matter. In particular, the QCD axion is capable of not only providing a dark matter candidate, but is also gives a natural explanation for the strong CP problem. Consequently, the detection of dark matter axions is of great interest as it would solve two of the most significant problems of modern physics. To this end, we introduce a new method to detect galactic dark-matter axions using dielectrics. When a dielectric interface is inside a strong parallel magnetic field, the oscillating axion field acts as a source of microwaves, which emerge in both directions perpendicular to the surface. These microwaves compensate for a discontinuity in the axion induced electric field. Crucially, the emission rate can be boosted by multiple parallel layers judiciously placed to achieve constructive interference. Starting from the axion-modified Maxwell equations, we calculate the efficiency of this new "layered dielectric haloscope” approach. This technique may prove useful in the well-motivated high-frequency range of 10-100 GHz (axion mass 40-400 ueV), where traditional cavity resonators have difficulties reaching the required volume. This would allow one to study axion dark matter generated by the topological defects, which occur if the reheating temperature after inflation was lower than the Peccei-Quinn scale. Unlike a cavity resonator it is possible for dielectric haloscopes to conduct a broadband search. In particular, we study the relation between the power generated and the bandwidth, the connection between the emission and reflection functions, the required placement precision for meter-scale disks, and the impact of small but non-vanishing axion velocities.

Speaker: Mr Alexander Millar (Max Planck Institute for Physics)

Slides Dielectric_Haloscopes_talk_Patras.pptx

17:55 → 18:20 The Sun and its Planets as detector for invisible matter

Abstract Gravitational lensing of invisible streaming matter towards the Sun could explain the puzzling solar flares and the unexplained solar emission in the EUV. One would expect a more pronounced solar activity at certain planetary positions. This is best demonstrated in the case of the 3 inner planets, with their relatively short revolution. We have analyzed the solar flares as well as the EUV emission. We observe statistically significant signals. An update of this work at the time of the workshop will be presented.

Speaker: Prof. Konstantin Zioutas (University of Patras / Greece)

Slides PATRAS12_SB_2016_final.pdf

18:20 → 19:00 Round table discussion

Wednesday, 22 June

09:00 → 09:35 Recent Progress in Neutrino Physics

Neutrino is one of the most abundant constituents of the Universe. Yet, its weakly interacting nature poses a challenge to the studies of its properties. Progress was slow until the recent discoveries of neutrino oscillation. At the center stage is the issue of the neutrino mass. In this talk, the recent progress and prospects of our quest for understanding the neutrino mass will be presented.

Speaker: Dr Kam-Biu Luk (University of California, Berkeley, and Lawrence Berkeley National Laboratory)

Slides PATRAS2016_Luk-v2.pdf

09:35 → 09:55 Relaxion with multiple axions

Recently proposed relaxion solution to the weak scale hierarchy problem involves an axion-like field which has hierarchical couplings. We discuss a scheme to generate the required hierarchical axion couplings (scales) from multiple axions, and present an explicit UV completed model realizing the scheme with high scale SUSY.

Speaker: Kiwoon Choi (CTPU/IBS)

Slides relaxion_choi.pdf

09:55 → 10:15 Searching for Dark Matter candidate with the AURIGA detector

We present a search for a new scalar particle, called moduli, performed using the cryogenic resonant-mass gravitational wave detector AURIGA. The existence of moduli is predicted by String Theory and may have significant contribution to the Dark Matter (DM) in our Universe. DM clusters under the galaxies gravitational effect, forming the so called galactic halo. The interaction of ordinary matter with a DM halo composed by moduli, causes the mass of electrons, me, and the fine structure constant, α, to oscillate in time. This implies the oscillation of solids with a frequency equal to the mass of the DM particle [Arvanitaki et al., Phys. Rev. Lett. 116, 031102 (2016)]. In particular, the putative signal would appear as a sharp peak (Δf ~ 1 mHz) in the sensitive band of AURIGA, some 100 Hz at about 1 kHz. We used high quality data, selected out of an acquisition of years of continuous running. The search sets upper limits at 95% CL on the moduli coupling to matter de < 10^(-4) (with respect to the gravitational force strength) around moduli masses m = 3.6⋅10^(-12) eV.

Speaker: Dr Antonio Branca (INFN Padova)

Slides Branca_talk.pdf

10:15 → 10:35 Dilaton as GIMP and Dilatonic Dark Matter

We discuss the importance of the dilaton in physics, in particular in cosmology. It naturally appears in almost all higher-dimensional unified theories as the fundamental scalar graviton which generates the fifth force. Moreover, it could become an excellent candidate of the dark matter as the gravitationally interacting massive particle (GIMP). We discuss how to detect the dilaton experimentally.

Speaker: Prof. Yongmin Cho (Konkuk University, Seoul)

Slides 05.ddms.pdf

10:35 → 11:05 Coffee break

11:05 → 11:30 Status of the ADMX-HF Extreme Axion Experiment

Axions are a leading dark matter candidate, and may be detected by their resonant conversion to a monochromatic RF signal in a tunable microwave cavity permeated by a strong magnetic field. The Axion Dark Matter eXperiment – High Frequency (ADMX-HF) serves both as an innovation platform for cavity and amplifier technologies for the microwave cavity axion experiment, and as a pathfinder for a first look at data in the 20–100 μeV (~ 4–25 GHz) range. A collaboration of Yale University, where the experiment is sited, the University of California Berkeley, Colorado University, and Lawrence Livermore National Laboratory, ADMX-HF is a small but highly capable platform where advanced concepts can be developed and vetted in an operational environment. The experiment is built on a superconducting solenoid magnet (9 T, 17.5 cm Ø x 40 cm) of high field uniformity, and a dilution refrigerator capable of cooling the cavity and amplifier to 25 mK. In its initial configuration, the microwave cavity is made of high purity electroformed copper, tunable between 3.6 – 5.8 GHz. The cavity is coupled to a Josephson Parametric Amplifier; JPAs are ideally suited for the 5 GHz range, being broadly tunable and exhibiting near-quantum-limited noise temperature. Construction and commissioning was completed in 2015, and the experiment embarked on its first data production run in January 2016, which will conclude in late summer. This talk will give an overview of the design and operational experience of the experiment, and a preliminary report on its first data. R&D oriented to significantly increase the sensitivity of the microwave cavity experiment will also be reviewed, including a squeezed-vacuum state receiver, very high-Q cavities, and photonic band-gap resonators. This work was supported under the auspices of the National Science Foundation, under grants PHY-1067242 and PHY-1306729, the Heising-Simons Foundation under grant 2014-182, and the U.S. Department of Energy by Lawrence Livermore National Security, LLC, Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Speaker: Ms Samantha Lewis (University of California Berkeley, ADMX-HF Collaboration)

Slides LewisPatras2016.pdf

11:30 → 11:50 Recent results and future plans of XMASS

XMASS-I, the first phase of the XMASS project, is dedicated to a direct dark matter search using nearly 1 tons of liquid xenon as target material. We have restarted the data taking in November, 2013 after the refurbishment of the detector in order to reduce the background significantly and been continuously taking data since then. We have recently submitted the results of annual modulation search with 359 live days x 832 kg of data accumulated. In this talk, the latest physics results and the future plans of the XMASS project will be presented.

Speaker: Byeongsu Yang (ICRR)

Slides Partras_2016_XMASS_Yang.pdf

11:50 → 12:15 Latest results from the DAMIC experiment

The DAMIC (Dark Matter in CCDs) is an experiment searching for low-mass dark matter particles employing fully-depleted charge-coupled devices. Using the bulk silicon of CCDs as the detector target, we expect to observe coherent WIMP-nucleus elastic scattering. In this contribution the main results about the background measurement and exclusion limits in the cross section-WIMP mass parameter space concerning the current setup of DAMIC installed at Snolab will be presented. The installation and expected results of DAMIC100, a detector with 100g of target silicon, the next configuration of the experiment, will also be discussed.

Speaker: Dr Diego Torres Machado (Federal University of Rio de Janeiro)

Slides slides-Diego-v1.pdf

12:15 → 12:40 The DEAP-3600 Dark Matter Direct Detection Experiment

DEAP-3600 is a single phase liquid argon (LAr) dark matter experiment, located 2 km underground at SNOLAB, in Sudbury, Ontario. The detector has 1 tonne fiducial mass of LAr. The target sensitivity to spin-independent scattering of 100 GeV WIMPs is 1$\times$10$^{-46}$ cm$^2$. The DEAP-3600 background target is <1 background events in the WIMP region of interest in 3 tonne-years exposure. The strategies to achieve this background are pulse shape discrimination to mitigate electron recoils, ultra-low radioactivity materials for detector construction to reduce neutron and alpha backgrounds, and in-situ sanding of the acrylic vessel to mitigate radon exposure of surfaces during construction and fabrication. Detector commissioning is underway and the WIMP search begins in 2016. This talk reports on recent progress from the DEAP-3600 experiment.

Speaker: Prof. Jocelyn Monroe (Royal Holloway, University of London and KEK Laboratory)

Slides 09.jmonroe_patras2016_deap3600.pdf

12:40 → 13:40 Lunch

13:40 → 14:00 Status and prospect of CDEX and China Jinping underground laboratory

The China Dark matter EXperiment (CDEX) pursues the direct searches of light WIMPs towards the goal of a ton-scale germanium detector array at the China Jinping Underground Laboratory (CJPL) in Sichuan,China. CJPL is the deepest operational underground laboratory in the world which have about 2400 m of rock overburden. Results from the CDEX-0 using a 20 g germanium detector array and the CDEX-1 using a 994 g pPCGe (p-type Point Contact Germanium) detector were reported. CDEX-10 employed a PCGe array of 10 kg target mass range is being tested in CJPL. CJPL-II laboratory is under construction which the hall volume is about 24 times more than the CJPL-I and will be finished by the end of 2016.

Speaker: Mr Hao Jiang (Tsinghua unviersity)

Slides 01.China_Jinping_underground_laboratory_and_CDEX_program_HaoJiang.pdf

14:00 → 14:20 Simulations of ultralight axion dark matter halos

Ultra-light axions (ULAs) are dark matter candidates which suppress the growth of perturbations on scales below their de Broglie wavelength and predict solitonic halo cores owing to their "quantum pressure" support. They therefore give rise to new phenomenology in large-scale structure formation and galaxy evolution, including a potential solution to the cusp-core and satellite problems. The nonlinear, non-relativistic dynamics of ULA halos can be numerically modeled by solving the Schroedinger-Poisson equations or, equivalently, the fluid equations with an additional quantum pressure term. Several approaches to simulate structure formation with ULA dark matter, both directly and semi-analytically, and some preliminary results will be presented.

Speaker: Prof. Jens Niemeyer (Goettingen University)

Slides 02.Patras2016_Niemeyer.pdf

14:20 → 14:40 Cosmological Relaxation of the Electroweak Scale

A new class of solutions to the electroweak hierarchy problem is presented that does not require either weak-scale dynamics or anthropics. Dynamical evolution during the early Universe drives the Higgs boson mass to a value much smaller than the cutoff. These solutions inherently require the existence of an axion coupled to the Higgs boson. I will review theoretical developments in this area and discuss experimental ways to probe this scenario.

Speaker: Surjeet Rajendran (UC Berkeley)

Slides Rajendran.pdf

14:40 → 15:00 Status of CUORE: an observatory for neutrinoless double beta decay and other rare events

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale double beta decay experiment based on TeO2 cryogenic bolometers that is currently in the last construction stage at the Gran Sasso National Laboratory (LNGS). Its primary goal is to observe neutrinoless double beta decay of 130Te, with a projected sensitivity reaching the inverted hierarchy region of the neutrino mass. Furthermore, thanks to the ultra-low background and large projected exposure, CUORE could also be suitable to other rare event searches, as the detection of solar axions or direct detection of dark matter. CUORE-0, a single-tower CUORE prototype consisting of 52 TeO2 bolometers and recently concluded, has served as a proof-of-concept of the CUORE technology. In this talk I will present the final results from CUORE-0 neutrinoless double beta decay search with a 9.8 kg·yr exposure of 130Te, and discuss the status and the physics potential of CUORE on different rare event searches.

Speaker: Mrs Maria Martinez (University of Rome - La Sapienza)

Slides Martinez_Patras16.pdf

15:00 → 15:20 Any Light Particle Search II (ALPS II)

The Any Light Particle Search II (ALPSII) is a Light Shining through a Wall (LSW) style experiment that will look for axion like particles with masses in the sub meV range. LSW experiments take advantage of the fact that in the presence of strong magnetic fields photons could theoretically couple to axion like fields. A constant flux of these fields can thus be generated by directing high power laser beams through a region of a strong magnetic field. The axion like field can then be isolated with a wall that allows it to pass, but blocks the laser. After the wall another strong magnetic field will cause the axion like field to convert back to a photon which can be observed by a photodetector. The interaction time between the laser and the magnetic field can be increased with an optical cavity before the wall which also increases the flux of the axion field through the wall. ALPSI used this technique to perform the most sensitive search up to that time for axion like particles. A second optical cavity behind the wall resonant with light from the first cavity and sharing the same spatial Eigenmode will increase the probability that the axion like field will reconvert to a photon. ALPSII will use this technique with ~100m high finesse optical cavities in 5T magnetic fields to measure the coupling constant between photons and the axion like particles with a sensitivity down to 10^-11/GeV. A smaller scale proof of concept experiment named ALPSIIa is currently being constructed with 10m cavities and no magnets. All of the optical systems related to ALPSIIa should be operational by the end of the year with data runs taking place at the beginning of 2017. Construction of the clean rooms for ALPSIIc will begin next year with the commissioning of the optics starting in 2018 and data runs in 2019. We will report on progress related to the experiment.

Speaker: Dr Aaron Spector (University of Hamburg)

Slides 05.ALPS_PATRAS_2016.pdf

15:20 → 15:40 Multiple-cavity detectors for axion dark matter search

Searching higher frequency regions for axion dark matter using microwave cavity detectors requires smaller size cavities as the resonant frequencies scale inversely with their radius. One of the intuitive ways to make an efficient use of a given magnet volume, and thereby to increase the experimental sensitivity, is to bundle multiple cavities together and combine their individual outputs ensuring phase-matching of the coherent axion signal. The Experiment of Axion Search aT CAPP (EAST-C) is a dedicated project to develop multiple-cavity systems at the Centre of Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) in Korea. Realistic design of the phase-matching mechanism has been extensively studied and an experimental demonstration has been successfully achieved using a double-cavity system. In this talk, a summary of the study and demonstration will be made and future plans on EAST-C project will be discussed.

Speaker: SungWoo YOUN (CAPP/IBS)

Slides Patras2016_YOUN.pptx

15:40 → 16:10 Coffee break

16:10 → 19:10 Poster session

16:10 Design of a Laser Frequency Stabilization for Cs Atomic Magnetometer

Speaker: Dongok Kim

Slides 2016_06_PATRAS_Dongok_v2.pdf

16:10 Measurements of quality factor of microwave cavities for axion search experiments

In cavity-based axion search experiments, the quality factor of microwave resonant cavities is an important parameter for improvement of sensitivity to the axion-to-photon coupling. One of the R&D efforts conducted at the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) is to develop high-Q cavities with frequency tuning systems. Using a 4K cryocooler and liquid helium, we measure the temperature dependence of Q values for cylindrical cavities of various materials. The results of the measurements are presented and future plans are discussed in this poster.

Speaker: Mr Saebyeok Ahn (KAIST/CAPP/IBS)

Slides Q_measurement_poster_PATRAS_새벽.pdf

16:10 Microwave resonator R&D in support of the ADMX-HF/Extreme Axion Experiment

The ADMX-HF/Extreme Axion Experiment platform was created to identify and resolve challenges for the microwave cavity experiment in the 2.5–25 GHz range (~ 10–100 μeV), develop new cavity and amplifier technologies, and serve as a data pathfinder in the high mass axion range. The University of California Berkeley is responsible for development of microwave resonators for the experiment; this poster will highlight three topics: 1. high-fidelity field mapping with the bead perturbation technique, coupled with simulations and metrology; 2. avenues to high-Q cavities, in particular R&D on superconducting thin-film cavities and Distributed Bragg Reflectors; and 3. Photonic Band Gap resonators to eliminate unwanted TE modes and accelerate the scan rate of the experiment. ADMX-HF/X3 is a collaboration of Yale University, UC Berkeley, Colorado University, and LLNL; the Berkeley effort is supported by the National Science Foundation, grant NSF PHY-1306729, and the Heising-Simons Foundation, grant 2014-182. S.M. Lewis acknowledges receipt of a Chancellor's Fellowship by the University of California Berkeley.

Speaker: Samantha Lewis (University of California, Berkeley)

Slides poster_final.pdf

16:10 Simulation study on optimization of cavity design for axion search experiments using COMSOL multiphysics

A conventional axion search experiment utilizes microwave resonant cavities, where axions are converted into photons under a strong magnetic field. Optimal cavity dimension is important to enhance signal power from the axion-to-photon coupling, to broaden the scan range, to minimize mode crossings, etc. An extensive study has been performed to optimize the dimensions of cylindrical cavities and frequency tuning systems using the COMSOL multiphysics simulation software. We introduce a figure of merit for this purpose, and present the results from the simulation study.

Speaker: Mr Junu Jeong (KAIST/CAPP/IBS)

Slides junujeong_2016patras.pdf

17:40 3He Gas Handling System and RF Discharge for Optical Pumping

Speaker: Younggeun Kim

Slides patras.pdf

17:40 Comsol Simulation of Modified Maxwell Equations with Axion Field

Speaker: Le Phuong Hoang

Slides Phuong_Patras_Poster_2016.pdf

17:40 Design and performance of a signal processing system for CULTASK experiment

CULTASK (CAPP Ultra Low Temperature Axion Search in Korea) is an experiment to search for the cosmic Axion using resonant cavities, targeting to be sensitive to a large range of microwave photons converted via the Primakoff effect in a very high magnetic field at an ultra low temperature. In order to detect very weak signal of 10^-24 W with a high signal-to-noise ratio, a careful system for signal processing has been designed and developed. The basic principle of the signal processing is a radio frequency (RF) transceiver with direct conversion to baseband, with a fast digitizer to process the amplified signal in real time for further Fourier transformation. The measurement results of a cryogenic amplifier chain and the signal processing system at room-temperature will be presented.

Speaker: Dr Young-Im Kim (Institute for Basic Science)

Slides 20160617_rfMeasurements_patras2016_v2.pdf

17:40 temp

Speaker: Mr Ben McAllister (The University of Western Australia)

Thursday, 23 June

08:40 → 09:25 ATLAS / CMS (tentative)

(tbd)

Speaker: Dr Alex Martyniuk (University College London)

Slides 01.PATRAS.pdf

09:25 → 09:50 A search for bosonic dark matter with the MAJORANA DEMONSTRATOR

The MAJORANA Collaboration is assembling an array of high purity Ge detectors to search for neutrinoless double-beta decay in Ge-76. The experiment consists of 44 kg of HPGe detectors (30 kg enriched in Ge-76) with a low-noise p-type point contact (PPC) geometry. They are operated deep underground within a compact shield constructed from lead and high purity copper. These technical specifications make it favorable to extend the measurement to low energies to open up the experiment's sensitivity to dark matter and axion searches. The first of two modules of detectors has been operating since June of 2015 and the second is under construction at the Sanford Underground Research Facility in Lead, SD. We present the results of searches for bosonic dark matter and other rare event searches using data from the commissioning and first physics runs that improve upon existing limits.

Speaker: Christopher O'Shaughnessy (University of North Carolina at Chapel Hill)

Slides PATRAS_OShaughnessy_June_2016_.pdf

09:50 → 10:15 Aharonov Bohm type experiments

We discuss the Aharonov-Bohm effect in the presence of hidden photons kinetically mixed with the ordinary electromagnetic photons. The hidden photon field causes a slight phase shift in the observable interference pattern. It is then shown how the limited sensitivity of this experiment can be largely improved. The key observation is that the hidden photon field causes a leakage of the ordinary magnetic field into the supposedly field-free region. The direct measurement of this magnetic field can provide a sensitive experiment with a good discovery potential, particularly below the meV mass range for hidden photons.

Speaker: Prof. Paola Arias (USACH, Santiago, Chile)

Slides 03.Patras2016_arias2.pdf

10:15 → 10:40 Commissioning of the ADMX Gen 2 Dark Matter Search

ADMX, the Axion Dark Matter Experiment, has recently undergone commissioning of the Gen 2 dark matter search, which should be significantly more sensitive to axion dark matter over a wider range of masses than previous axion cavity searches. I will discuss the technical details of the new subsystems: dilution refrigeration, quantum electronics, and additional channels. Commissioning data from these systems will be presented, and I will talk about the first steps in a DFSZ-sensitive program to find the axion.

Speaker: Dr Gray Rybka (University of Washington)

Slides 04.2016_06_rybka_patras_admx.pdf

10:40 → 11:10 Coffee break

11:10 → 11:30 A new QCD dark matter axion search using a dielectric resonant cavity

Peccei-Quinn mechanism that can explain the absence of CP-violating effects in quantum chromodynamics (QCD). Axions could also provide the cold dark matter of the universe and as such are among the few particle candidates that solve simultaneously two major problems of nature. All existing experimental efforts focus on a range of axion masses below 20 ueV which is motivated by the traditional re-alignment mechanism of the axion field. If the Peccei Quinn symmetry was restored after inflation, decaying topological defects could lead to an axion population providing all of the cold dark matter with an axion mass in the range of 100–300 ueV. A new project based on the idea of axion photon conversion at the transition between two media with different dielectric constants will be presented. With transition layers inside a static magnetic field parallel to the surface of the transition layers, photons in the microwave regime could be generated by the hypothetical dark matter axion field. A significant boost in photon conversion can be achieved when using several layers with alternating dielectric constants. The additional surfaces are forming coupled resonant cavities and could enhance the axion-photon conversion rate significantly. A resonator with a boost factor of ~10^5 within a magnetic field of order 10T could be enough to achieve an axion-photon conversion rate within a reasonable volume to be unambiguously detected with state of the art radiometer technology within a reasonable time per frequency band. The experimental idea and the proposed design for an experiment will be discussed. First results from measurements of the expected preamplifier noise and the microwave radiation transmission and reflection behavior of a prototype resonant dielectric cavity will be discussed. The prospects for reaching a sensitivity enough to cover the parameter space predicted for QCD dark matter axions with mass in the range 40-400 ueV will be presented.

Speaker: Dr Javier Redondo Martin (Zaragoza U / MPP Munich)

Slides 160602_mad_maxion_160623.pdf

11:30 → 11:50 Dark Matter Searches for Monoenergetic Neutrinos Arising from Stopped Meson Decay in the Sun

Dark Matter can be accumulated by the scattering with solar nuclei. In the center of the Sun, Dark Matter annihilations provide detectable signals. Research investigated these signals with two steps; 1. hadronization after annihilation 2. hadronic shower process in the Sun. From the first step, neutrinos are generated and previous works focused on it. However, neutrinos from hadronic shower also can be competitive signals as showers create huge amounts of pions. We improve previous works as consider hadronic shower process containing pion and kaon decays. We apply our results at liquid-scintillation, liquid argon, and water Cherenkov detectors and show competitive sensitivities at few-GeV dark matter masses.

Speaker: Mr In Seongjin (Sungkyunkwan University)

Slides PATRAS_Meeting.pdf

11:50 → 12:15 STAX. A search for axion-like particles with sub-THz photons

We discuss an improved detection scheme for a light-shining-through-wall (LSW) experiment for axion-like particle searches [Capparelli, Cavoto, Ferretti, Giazotto, Polosa and Spagnolo, arXiv: 1510.06892]. We propose to use: extremely intense photon fluxes (from 100 kW to 1MW) from gyrotron sources at frequencies around 30 GHz; single photon detectors in this frequency domain, with efficiency ≈ 1, based on transition-edge-sensors (TES); high quality factor Fabry-Perot cavities in the microwave domain (Q ≈ 10^4-10^5), both on the photon-axion conversion and photon regeneration sides. We compute that present laboratory exclusion limits on axion-like particles might be improved by at least four orders of magnitude for axion masses ≤ 0.01 meV.

Speakers: Prof. Antonio Davide Polosa (La Sapienza and INFN Rome), Dr Francesco Giazotto (NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore), Dr Gianluca Cavoto (INFN Rome), Dr Jacopo Ferretti (La Sapienza and INFN Rome), Dr Ludovico Capparelli (UCLA), Dr Paolo Spagnolo (INFN Pisa)

Slides Ferretti_Jeju.pdf

12:15 → 12:40 Beyond the Dark matter effective field theory and a simplified model approach at colliders: Higgs portal DM as examples

Direct detection of and LHC search for the singlet fermion dark matter (SFDM) model with Higgs portal interaction are considered in a renormalizable model where the full Standard Model (SM) gauge symmetry is imposed by introducing a singlet scalar messenger. In this model, direct detection is described by an effective operator m_q \bar{q} q \bar{\chi} \chi as usual, but the full amplitude for monojet + \not E_T involves two intermediate scalar propagators, which cannot be seen within the effective field theory (EFT) or in the simplified model without the full SM gauge symmetry. We derive the collider bounds from the ATLAS monojet + \not E_T as well as the CMS t\bar{t} + \not E_T data, finding out that the bounds and the interpretation of the results are completely different from those obtained within the EFT or simplified models. It is pointed out that it is important to respect unitarity, renormalizability and local gauge invariance of the SM.

Speaker: Dr Ko Pyungwon (School of Physics, KIAS, Seoul 130-722, Korea)

Slides 08.BeyondEFT_patras2016_pko.pdf

12:40 → 17:40 Excursion to Tropical Hallim Park

Hallim park is one of the most popular tourist spots on Jeju Island with nine fantastic theme parks full of exotic sentiment. Hyeopjae beach and an olle trail nearby are also enjoyable.

18:10 → 21:40 Conderence Banquet

Friday, 24 June

08:55 → 09:15 The CAST-CAPP/IBS Detector Project: Progress and Challenges

The CAST-CAPP/IBS Detector, a joint effort between the CERN Axion Solar Telescope (CAST) collaboration [1] and the Center for Axion and Precision Physics Research (CAPP/IBS) [2], has made considerable progress towards the design and initial installation of rectangular RF cavities inside the bore of the 9T CAST dipole magnet. The final goal of this project, currently in an R&D stage, is a haloscope search [3] for cold dark matter axions in the ~21 to 25 μeV mass range (~5 to 6 GHz). While a limited, exploratory installation is scheduled for mid June 2016, many challenges and uncertainties remain. These uncertainties come from timely completion of the integration into the CAST magnet; timely delivery of rectangular cavities; the sheer ability of properly placing and cooling cavities inside the magnet cold bores, while being able to recover them; the presence of mechanical instabilities; the proper placement and configuration of low temperature electronics in a partially unknown environment; etc. This installation is thus not guaranteed to be on time for this workshop. Nevertheless we would like to present the progress that has occurred in cavity design and fabrication, in the development of tuning schemes, in the integration of the project into the CAST magnet, and more. [1] CAST Collaboration, K. Zioutas et al., Phy. Rev. Lett. 94 (2005) 121301. [2] http://capp.ibs.re.kr/html/capp_en/ [3] P. Sikivie, Phys. Rev. Lett. 51, 1415 (1983).

Speaker: Dr Lino Miceli (IBS Center for Axion and Precision Physics)

Slides 01.2016-06-24_PATRAS_LMiceli.pdf

09:15 → 09:35 Search for dark particles at Belle

The dark photon, $A′$, the dark Higgs boson, $h′$, and the light vector gauge boson, $\omega'$, are hypothetical constituents featured in a number of recently proposed Dark Sector Models. We will present a search for these particles in the so-called Higgs-strahlung, radiative, and neutral $D-$meson decay channels. Using the data set collected, by the Belle experiment, we present our results for the prompt decay and displaced vertex decay hypothesis when allowed.

Speaker: Prof. Eunil Won (Korea University)

Slides 02.Patras2016.pdf

09:35 → 10:00 Latest results from IceCube

The latest results from IceCube, the world's largest neutrino telescope, will be presented. A particular focus will be set on the indirect search for dark matter and the potential to observe axion signatures in supernova neutrino bursts.

Speaker: Dr Carsten Rott (Sungkyunkwan University, Seoul)

Slides 03.Rott_Patras2016_IceCube.pdf

10:00 → 10:20 A new detector at the LHC to search for millicharge particles

The experiments presently at the LHC have only a limited sensitivity to possible exotic particles which carry only a fraction of the the electron charge. Such particles can follow from extensions beyond the Standard Model with new U(1) groups. A recent proposal was made to install a dedicated experiment consisting of large blocks of scintillators in the underground caverns, behind a thick concrete wall. This detector would be sensitive to charges down to a few times 10^-3 Q_e and to millicharge particles with a mass up to about 100 GeV, based on the HL-LHC data statistics. Such a detector is now being planned to be installed in the next few years and will be presented.

Speaker: Gabriel Magill (Perimeter Institute for Theoretical Physics)

Slides 04.PatrasGabrielMagill.pdf

10:20 → 10:40 Dark matter research cluster based on computational science

Let me introduce the convergence research cluster for dark matter which is supported by National Research Council of Science and Technology. The goal is to build research cluster of nationwide institutes from accelerator-based physics to astrophysics. The methodology is to do computational science using infrastructures at KISTI (Korea Institute of Science Technology Information) and KASI (Korea Astronomy and Space Science Institute). What we need for dark matter will be discussed.

Speaker: Prof. Kihyeon Cho (KISTI)

Slides 05.axion16_dm_062416.pptx

10:40 → 11:10 Coffee break and sandwiches

11:10 → 11:30 Preliminary data analysis of OSQAR-CHASE results

The OSQAR experiment has been extended to the quest of chameleon particles, i.e. particles with environment-dependent mass, from the search of a magnetic afterglow effect. OSQAR-CHASE (chameleon afterglow search) has been run in 2015 using one spare LHC dipole providing a 9 T transverse magnetic field with an 18.5 W DC laser and state-of-the art CCD detector. The principle of the experiment will be reminded. All possible sources of photons have been thoroughly scrutinized and dedicated simulations of the expected signal performed. Preliminary analysis of recorded data will be presented and discussed. An overview of recent experimental results on Chameleon search by similar or other methods will also be given.

Speaker: Dr Miroslav Sulc (Technical University of Liberec)

Slides 06.OSQAR_CHASE_12_patras_2016.pptx

11:30 → 11:50 New Coupling Constrains on Light Bosons Beyond the Standard Model

Searches for anomalous spin- and velocity-dependent forces (SVDF) have drawn considerable attention in the past few decades. Various theories beyond the Standard Model predict very light, weakly coupled scalar, pseudo- scalar, vector, or axial-vector bosons. Because of theirs weakly coupling, they could escape detectors, and not founded in normally high energy experiments. The coupling strengths have be constrained by astrophysics, cosmology, and laboratory experiments. We proposed a new method to constrain the coupling constants of $g_Vg_A$ and $g_A^2$ by using polarized 3He gas. A record constrain was achieved by using the new method.

Speaker: Prof. Changbo Fu (Shanghai Jiaotong Univeristy)

Slides 07.5th-Force-Korea-20160624-fcb.pptx

11:50 → 12:10 Simulating axion string-wall networks

The axion mass should be cleanly related to the axion dark matter density through the efficiency of cosmological axion production, allowing constraints to be placed on the mass. A signifcant source of cosmological axion production is the unstable network of axionic cosmic strings and domain walls, regions where the axion field is forced to rise above its vacuum expectation value for topological reasons, which arises from phase transitions in the axion's cosmological history. Accurate simulations of these string-wall networks are crucial for predicting cosmological axion production. However, correctly implementing the string cores has been a major hurdle for simulations of axion string-wall networks. In this talk, I will present a new algorithm for treating the string cores in axion string-wall network simulations.

Speaker: Prof. Leesa Fleury (University of British Columbia, Vancouver)

12:10 → 12:30 High and low mass axion haloscopes at UWA

The Frequency and Quantum Metrology (FQM) group at UWA is in the process of constructing a haloscope experiment (ORGAN) designed to probe for axions at 26.6 GHz. The motivation for this search is to perform the first direct test of the Beck result [1] which suggests axions exist at this frequency. There are many technical issues and optimisations that must be considered in the design of such a high mass axion haloscope, which are typically considered infeasible. We have developed new techniques to increase the sensitivity of such searches. These new techniques were motivated by a rigorous theoretical treatment of axion haloscope theory, where the detecting structure differs from a right cylindrical cavity embedded centrally in a magnetic field [2]. By examining such systems in detail we found that the common assumption of equal electric and magnetic axion-resonant photon couplings is incorrect in any system which is not centrally symmetric with respect to the applied external magnetic field. When considering explicitly the magnetic coupling of axions to resonant photons, it is possible to achieve improved sensitivity by employing novel cavity geometries and experimental setups. We discuss the ORGAN experiment and how it will employ these techniques to improve sensitivity. A further consequence of the explicit treatment of the axion magnetic coupling is the possibility of sensitive low mass axion haloscopes employing lumped 3D LC resonators (known commonly as re-entrant cavities [3,4]), with separated magnetic and electric fields. Such structures resonate at frequencies inherently lower than those achievable in an empty cavity. In these systems it is critical to explicitly treat both the axion electric and magnetic couplings in order to accurately calculate sensitivity. We present a proposal for such a low mass haloscope. [1] C. Beck, Phys. Rev. Lett. 111, 231801 (2013), http://link.aps.org/doi/10.1103/PhysRevLett.111.231801. [2] B. T. McAllister, S. R. Parker, M. E. Tobar, Phys. Rev. Lett (accepted, in production). N.B: Longer pre-print version available on arXiv. https://arxiv.org/abs/1512.05547 [3] Y. Fan, Z. Zhang, N. Carvalho, J.-M. Le Floch, Q. Shan, and M. Tobar, IEEE Transactions on Microwave Theory and Techniques 62, 1657 (2014), arxiv.org/abs/1309.7902. [4] J.-M. Le Floch, Y. Fan, M. Aubourg, D. Cros, N. C. Carvalho, Q. Shan, J. Bourhill, E. N. Ivanov, G. Humbert, V. Madrangeas, and M. E. Tobar, Review of Scientific Instruments 84, 125114 (2013), http://dx.doi.org/10.1063/1.4848935.

Speaker: Mr Ben McAllister (School of Physics, The University of Western Australia)

Slides PATRAS.pptx

12:30 → 12:50 Formation of Axion Miniclusters

We will discuss the formation of axion dark matter miniclusters during the QCD phase transition in numerical simulations. The existence of axion miniclusters might be crucial to the outcome of axion dark matter direct detection experiments but also of possible indirect signatures. For a detailed description of these effects the miniclusters properties, such as mass spectrum, number density and density profile, need to be known, which, in turn, depend crucially on the density contrast of the axion field previous to the gravitational collapse. Our simulations indicate that the inclusion of strings and domain walls puts a lot of fluctuation power in scales smaller than the horizon at the time of the QCD phase transition. These can collapse into a larger number of miniclusters of much smaller mass than previously consider.

Speaker: Dr Javier Rendondo (Universidad Zaragoza)