Name: Paolo Agnes
University: Univ Paris VII - Laboratoire APC (Paris, FR)
Abstract title: g4ds, the DarkSide simulation tool
Abstract: The DarkSide experiment is desgined for the direct detection of WIMPs by means of a double phase liquid
argon TPC, inserted inside a double system of active vetoes. The current detector is running with a 50 kg fiducial
mass underground argon fill and a larger detector is foreseen in near future. We developed a Geant4 based simulation
tool which includes the full geometry description of the detectors, takes care of the particle tracking and reproduces
at the percent level the detector response. This code includes an effective model for the recombination probability
of electron-ion pairs, which determines the ratio between ionization and scintillation for a any given interaction.
The code has been used for multiple purposes, as the search for reconstruction induced biases, the test of several
x--y reconstruction algorithms, the evaluation of the neutron bakground for the present and future phase, the veto
efficiency studies.
Name: Haipeng An
University: Caltech
Abstract title: Searching for dark photon with dark matter direct detection experiments
Abstract: Dark matter detectors built primarily to probe elastic scattering of WIMPs on nuclei are also precise
probes of light, weakly coupled, particles that may be absorbed by the detector material. In this talk, I will show
that the dark matter direct detection experiments can be used to search for dark photons assuming that they comprise
the dominant fraction of dark matter, as well as the dark photons emitted from the Sun.
Name: Michael Baker
University: University of Mainz
Abstract title: The Coannihilation Codex
Abstract: We present a general classification of minimal models where Dark Matter coannihilates with another
particle, X. Besides this new particle, such coannihilation processes typically require the existence of a
mediator, M. Assuming tree-level and renormalizable interactions we construct all possible Dark Matter, X
and M field content which respects gauge and Lorentz invariance. Using our framework one can identify the
main categories of LHC signatures associated with coannihilation. We discuss the different aspects of these
signatures, mentioning new possible topologies that could be explored at colliders.
Name: Pierluigi Belli
University: INFN - Roma Tor Vergata
Abstract title: DAMA/LIBRA results and perspectives
Abstract: The DAMA/LIBRA set-up (about 250 kg highly radiopure NaI(Tl)) is running deep underground at
the Gran Sasso Laboratory. The positive results in terms of the model independent Dark Matter annual
modulation signature and the results of recent investigations on possible diurnal effects and their
implications will be summarized. Presently DAMA/LIBRA is in data taking in a new configuration
(DAMA/LIBRA-phase2) with lower energy threshold. Results, implications and perspectives will be
addressed.
Name: Ethan Bernard
University of California, Berkeley
Abstract title: Studies of Two-Phase Xenon Detector Response with the PIXeY Experiment
Abstract: Two-phase xenon detectors play a central role in the modern search for interactions of dark matter with
baryonic matter. We present new measurements of two-phase xenon detector response, including electron/nuclear
recoil discrimination, electron extraction efficiency, charge and light yields, and energy resolution. We also
describe the use of 37Ar as a calibration source for energies as low as 270 eV.
Name: Tomasz Biesiadzinski
University: SLAC National Accelerator Laboratory
Abstract title: First Results From The LZ System Test Platform
Abstract: The LUX-ZEPLIN (LZ) experiment will push the search for weakly-interacting dark matter particles
to unprecedented sensitivity, beyond the current generation of experiments like LUX. This is achieved in
multiple ways: reducing various sources of background, adding an outer detector system to veto and monitor
residual backgrounds, increasing the mass of the liquid Xe detection medium, more thorough calibration,
and improving background discrimination. An LZ system test platform has been constructed at the SLAC
National Accelerator Laboratory in order to develop and validate technologies required by LZ. The platform
will assure that LZ can meet its high voltage and purification circulation requirements as well as test
calibration source injection, purity monitoring, and chemical sampling systems. An overview of the test
platform will be presented along with results from its first runs.
Name: Julien Billard
University: IPNL/CNRS
Abstsract title: Search for the low-mass WIMPs with the EDELWEISS III experiment
Abstract: The EDELWEISS-III experiment is a direct search for WIMP dark matter that uses an array of
twenty-four 800 g heat-and-ionization cryogenic detectors fully covered with interleaved electrodes for
the rejection of near-surface events. An 8-month search has been recently concluded. Detector performances
and in particular the improvement of experimental resolutions relative to the previous phase of the experiment
has made possible to reduce the analysis threshold down to 2.4 keV nuclear recoils, and extend significantly
the sensitivity to lower WIMP masses. We will present the limit obtained on the spin-independent WIMP-nucleon
cross-section from a fiducial exposure of 582 kg.day. The present limitations and the future prospects of the
experiment will be discussed, with the emphasis on the important gain in sensitivity achievable in the near
future for WIMP within the mass range from 1 to 20 GeV range, notably by using the Luke-Neganov amplification
of the heat signal and improved heat sensors, to reduce experimental thresholds.
Name: Kimberly Boddy
University: University of Hawaii
Abstract title: Models of Self-Interacting Dark Matter
Abstract: Despite the remarkable success of the standard cosmological model with collisionless, cold dark
matter (CDM), there are discrepancies between CDM simulations and observations of the small-scale structure
of the Universe. Over a wide range of astrophysical systems (from dwarf galaxies to galaxy clusters), dark
matter halos have lower central densities and shallower central profiles than those predicted by CDM
simulations. Allowing dark matter to have large self interactions can bring simulations in line with
observations across all scales. We consider a class of self-interacting dark matter models for which
dark matter is in a hidden sector and charged under a hidden gauge: an abelian U(1) or a non-abelian
SU(N). For the abelian case, dark matter may interact via exchange of a massive dark photon, or the
dark sector may be composed of dark atoms, analogous to hydrogen. For the non-abelian case, dark
matter may undergo confinement in the early Universe to form dark composite particles. These models
allow dark matter to have large elastic scattering cross sections, while yielding the observed relic
abundance. Additionally, inelastic processes may provide dark-matter explanations for other
astrophysical phenomena, such as the recently observed 3.5 keV X-ray line.
Name: Mark Boulay
University: Carleton University
Abstract title: DEAP-3600 Dark Matter Search with Argon
Abstract: The DEAP-3600 experiment will search for dark matter particle interactions on 3.6 tonnes of liquid argon at SNOLAB.
The argon is contained in a large ultralow-background acrylic vessel viewed by 255 8-inch photomultiplier tubes. Very good
pulse-shape discrimination has been demonstrated for scintillation in argon, and the detector has been designed to allow
control of (alpha,n) and external neutron recoils, and surface contamination from 210Pb and radon daughters, allowing an
ultimate sensitivity to spin-independent scattering of 10^{-46} cm^{2} per nucleon at 100 GeV mass. The detector is
expected to begin collecting low-background data in 2016; the current status of the experiment will be presented.
Name: Nassim Bozorgnia
University: GRAPPA, University of Amsterdam
Abstract title: Dark matter direct detection predictions from hydrodynamic simulations
Abstract: The dark matter density and velocity distribution at the position of the Earth are important parameters in the
interpretation of data from direct detection experiments. I will discuss the local dark matter distribution of Milky
Way-like galaxies obtained from the high resolution EAGLE hydrodynamic simulation. To make reliable predictions for
direct detection searches, we identify simulated haloes which satisfy the Milky Way observational constraints. I will
present an analysis of direct detection data, using the dark matter distribution of the selected Milky Way-like simulated
galaxies.>
Name: James Bullock
University: UC Irvine
Abstract title: Cold dark matter controversies and self-interacing dark matter
Abstract: I will provide an overview of the Too Big to Fail/mass-deficite problem in CDM. I will then discuss
self-interacting dark matter as an alternative and discuss ways forward for constraining the self-interaction
cross section of dark matter using cosmological simulations.
Name: Benjamin Brubaker
University: Yale University
Abstract title: Searching for Dark Matter Axions with ADMX-HF
Abstract: The axion is a well-motivated cold dark matter candidate first postulated to explain the absence of
CP violation in strong interactions. Dark matter axions may be detected via their resonant conversion into
photons in a high-Q microwave cavity permeated by a strong magnetic field. The Axion Dark Matter eXperiment
(ADMX) has used this technique to exclude axion models in the few micro-eV mass range, but most of axion
parameter space has remained inaccessible to experiment. By incorporating a dilution refrigerator and
Josephson parametric amplifier into an axion experiment for the first time, ADMX-HF (high-frequency),
a newly operational experiment at Yale, is poised to set the first limits in the axion model band around
20 micro-eV (5 GHz). ADMX-HF will serve as both a pathfinder search for high-mass axions and an innovation
test-bed. My talk will cover the design of ADMX-HF, preliminary results from an initial run, and R&D e
fforts aimed at pushing axion detection to higher masses and weaker couplings.
Name: Sheldon Campbell
University: University of California, Irvine
Abstract title: Determining Sensitivity of Astrophysical Anisotropy Signals to Dark Matter Annihilation
Abstract: Significant theoretical progress on the statistical uncertainty of angular power spectrum measurements
of high-energy astrophysical sources has recently been achieved. The implications of these results are discussed
in the context of using anisotropy methods to detect dark matter annihilation, and how such observations would
shed light on dark matter's nature.
Name: Clara Cuesta
University: University of Washington
Abstract title: Status of the ANAIS experiment
Abstract: ANAIS (Annual modulation with NaI Scintillators) is a project aiming to set up at the Canfranc
Underground Laboratory (LSC), a large scale NaI(Tl) experiment in order to explore the DAMA/LIBRA annual
modulation positive result using the same target and technique. Three 12.5 kg each NaI(Tl) crystals
provided by Alpha Spectra are currently taking data at the LSC (ANAIS-37) . The comparison of the background
model for the ANAIS-37 prototypes with the experimental results will be presented. The high light collection
efficiency obtained with these prototypes allows to anticipate an energy threshold of the order of 1 keVee.
Preliminary estimates of trigger efficiency at very low energy and the overall status of the experiment
will also be presented.
Name: Prisca Cushman
University: University of Minnesota
Abstract title: CDMSlite Results from Soudan
Abstract: The CDMS Low Ionization Threshold Experiment refers to the operation of one of the SuperCDMS
germanium detectors at high voltage. The number of phonons are amplified via the Luke effect, effectively
reducing the threshold. Results are presented from the second CDMSlite run with an exposure of 70 kg days,
which reached an energy threshold for electron recoils as low as 56 eV. New parameter space for the WIMP-nucleon
spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c. Prospects from CDMSlite
Run 3 and plans for the SNOLAB implementation will be discussed.
Name: Alex Drlica-Wagner
University: Fermilab
Abstract: The population of Milky Way satellite galaxies includes the least luminous, least chemically
evolved, and most dark matter dominated galaxies in the known universe. Due to their proximity, high dark
matter content, and lack of astrophysical backgrounds, dwarf spheroidal galaxies are promising targets
for the indirect detection of dark matter via gamma rays. Prior to 2015, roughly two dozen dwarf spheroidal
galaxies were known to surround the Milky Way. From combined observations of these objects, the dark matter
annihilation cross section has been constrained to be less than the generic thermal relic cross section for
dark matter particles with mass < 100 GeV. Since the beginning of 2015, new optical imaging surveys have
discovered over twenty new dwarf galaxy candidates, potentially doubling the population of Milky Way satellite
galaxies in a single year. I will discuss recent optical searches for dwarf galaxies, focusing specifically
on results from the Dark Energy Survey (DES) and the implications for gamma-ray searches for dark matter
annihilation with the Fermi Large Area Telescope.
Andrzej Drukier
University: OKC, Stockholm University, Sweden/LEN Inc, Warsaw Poland
Abstract title: Chemically amplified detectors for dark matter
Abstract: We are developing a new class of detectors for neutral and weakly interacting particles such as neutrons,
neutrinos, and dark-matter candidates. The detection is based on the interaction of the particles with nuclei of
the detector by means of room-temperature bolometry. Small amounts of energy deposited into nano-scale grains
trigger a release of chemical energy, leading to a “nano-explosion”. We used combined electromagnetic pulse,
acoustic and optical read-out techniques for read-out of such RT-bolometers. A “nano-explosion” generates an
overpressure, sonic boom, which can be detected acoustically and detectable burst of photons. We are interested
in very rare events and the coincidence detection of at least two quantities has been used to reject artifacts.
This talk describes the read-out schemes developed for such chemically amplified detectors aka RT-bolometers. A
particular implementation is using enzymatic reactions, wherein catalase reduce H2O2 in {x H2O2 + (1-x)H2O}, with
x = 20-40%. We expect that provided appropriate funds, a 1 ton detector will be deployed by the end of 2017 and
a 50 ton detector in late 2019. The expected performances are about a 3.5 logs better count-rate than LUX. In
parallel, the 1 ton “directional” detector will be developed.
Name: Alden Fan
University: UCLA
Abstract title: Results from DarkSide-50 with Underground Argon
Abstract: DarkSide-50 is a direct dark matter detection experiment located underground at Gran Sasso National
Laboratory in Italy. The experiment consists of a 50 kg dual-phase argon Time Projection Chamber (TPC) surrounded
by a 30 tonne liquid scintillator neutron veto and a 1 ktonne water Cherenkov detector. The TPC is currently filled
with argon obtained from underground sources, which is significantly reduced in 39Ar. DarkSide-50 has made the most
sensitive measurement of the 39Ar depletion in underground argon and performed a WIMP search using data from 70
live-days, setting the strongest limit to date on the WIMP-nucleon elastic scattering cross section with an argon
target. Overviews of the recent science results and current status of the DarkSide-50 experiment will be presented.
Name: Vera Gluscevic
University: Institute for Advanced Study, Princeton
Abstract title: Can We Identify the Theory of Dark Matter with Direct Detection?
Abstract: We forecast prospects for identifying the correct theory of dark matter-nucleus interaction with
upcoming measurements from direct detection experiments. Our main results show that a strong dark matter
signal on Generation-2 xenon and germanium experiments would have enough discrimination power to reconstruct
the momentum dependence of the interaction, and therefore rule out entire classes of dark-matter models.
However, zeroing in on a correct UV completion will critically depend on the availability of measurements
from a wide variety of nuclear targets (including iodine and fluorine) and on the availability of low-energy
recoil measurements. This study highlights and quantifies complementarity amongst different experimental
designs and targets, providing a roadmap for future searches, and also demonstrates the need for a joint
and agnostic data analysis in case a signal is observed.
Name: Scott Hertel
University: UC Berkeley
Abstract title: Improved and Expanded Limits from the LUX Experiment
Abstract: We present an improved analysis of the LUX experiment's 2013 exposure, placing new limits on
spin-independent and spin-dependent WIMP-nucleon interactions. This improved data treatment is also
used to constrain a generalized set of effective field theories describing possible WIMP-nucleus
interactions. We detail specific analysis improvements, including single-photon calibration at the
signal wavelength, improved event-reconstruction algorithms, and a profile likelihood method
including a background model for events originating on detector surfaces. Low-energy calibrations
employing tritium beta decay and a deuterium-deuterium neutron beam inform our analysis. This nuclear
recoil calibration extends down to 1 keVr, contributing to significant improvements in cross-section
limits, particularly at low WIMP masses. Finally we will describe the status of an ongoing 300-liveday
exposure.
Name: Dongqing Huang
University: Brown University
Abstract title: Ultra-low Energy Calibration of LUX detector with D-D neutron, Tritium, and 127Xe
Abstract: The LUX dark matter experiment is a 350 kg dual-phase time-projection chamber operating at the
4850 ft level of the Sanford Underground Research Facility in Lead, SD, USA. We present a new technique
for nuclear recoil (NR) calibration using multiple scattering of mono-energetic 2.45 MeV neutrons. We
have obtained a precision calibration of liquid xenon at energies down to 1.1 keVnr for light yield and
0.7 keVnr for charge yield. We also present absolute calibrations of electron recoil (ER) using tritium
beta and 127Xe electron capture events at energies down to 190 eVee. These in situ energy calibrations,
using D-D neutron, tritium, and 127Xe sources, represent the lowest energy NR and ER that have been
explored in liquid Xe and are accompanied by a significant improvement in calibration uncertainty.
Name: Aldo Ianni
University: Canfranc Underground Laboratory
Abstract title: The Canfranc Underground Laboratory
The Laboratorio Subterraneo de Canfranc (LSC) is the second largest Deep Underground Laboratory in Europe.
It is located in the Spanish Pyrenees at 1100 meters above sea level at the border between Spain and France.
About 1600 square meters are available underground for experimental activities. LSC has about 850 meters of
rock overburden with a residual cosmic rays flux of 4x10^-3 /m^2/s. The radon level underground is kept at
50-80 Bq/m^3 by a ventilation system with fresh air input of some 19000 m^3/h in the main experimental Hall.
The underground infrastructure includes a radon abatement system, a clean room, a workshop and a low counting
laboratory equipped with seven high-purity germanium gamma spectrometers. The underground infrastructure is
completed by an external building with offices, a chemistry and electronics laboratory. The main research
activities at LSC are on direct detection of dark matter and neutrinoless double beta decay. Direct dark
matter is searched for with an array of NaI(Tl) scintillators (ANAIS) and with a 2-ton liquid argon TPC
(ArDM). Neutrinoless double beta decay is searched for with a high pressure TPC using Xe gas enriched
in 136Xe (NEXT). More research activities are carried out at LSC on low counting techniques, geophysics
and biology. In the talk the LSC will be presented and the status of the experimental activities will be
reviewed.
Name: Xiangyang Ju
University: University of Wisconsin
Abstract title: Search for BSM physics including dark matter at ATLAS
Abstract: The increased centre-of-mass energy of the proton-proton collisions of the LHC run 2 gives a unique
opportunity to extend the sensitivity to the production of particles not foreseen by the Standard Model. This
talk summarises recent ATLAS results on BSM searches. Although the focus is on searches for production of DM
particles, results include searches for heavy resonances in many final states and for production of supersymmetric
particles.
Name: Chris Kelso
University: University of North Florida
Abstract: Title: Halo simulations with baryons and direct detection of dark matter
Abstract: The spatial and velocity distributions of dark matter in the Milky Way Halo affect the signals expected to
be observed in searches for dark matter. Results from direct detection experiments are often analyzed assuming a
simple isothermal distribution of dark matter, the Standard Halo Model (SHM). Yet there has been skepticism regarding
the validity of this simple model due to the complicated gravitational collapse and merger history of actual galaxies.
We compare the SHM to the results of detailed simulations of structure formation to investigate whether or not the SHM
is a good representation of the true WIMP distribution in the analysis of direct detection data. We examine two
Milky Way-like galaxies from the MaGiCC simulations of galaxy formation, obtained in simulations run a) with dark
matter only and b) with baryonic physics included. The inclusion of baryons drives the shape of the DM halo to
become more spherical, and renders the SHM a better approximation. We conclude that the SHM is in fact a good
approximation to the true dark matter distribution for the purpose of dark matter direct detection calculations.
Name: Michael Leyton
University: Royal Holloway, University of London / MIT
Abstract title: Directional Detection with the DMTPC Experiment
Abstract: Directional reconstruction provides a unique way to positively identify signal interactions
induced by dark matter particles, thanks to the motion of the earth through the galactic dark matter halo.
Directional information can additionally serve as a powerful discriminant against neutron (and neutrino-induced)
backgrounds that have the same final-state signature as a signal interaction. The Dark Matter Time Projection
Chamber (DMTPC) collaboration uses gas-based TPC technology, with both optical and charge readout, to measure
the directional anisotropy of nuclear recoils induced by particles traversing the detector volume. Here, we
present preliminary results from recent calibration and surface running of the cubic-meter DMTPC detector,
in addition to background rejection and directional sensitivity studies.
Name: Junsong Lin
University: University of Oxford
Abstract: Title: A phonon-scintillation detector operating at milli-Kelvin temperature with low-temperature photomultiplier readout
Abstract: A phonon-scintillation detector for rare event searches, equipped with an NTD-Germanium sensor to determine the energy
channelled into the phonon system and a low-temperature photomultiplier for detecting scintillation photons, was demonstrated.
The PMT (Hamamatsu, model R8520-06) powered by a Cockcroft-Walton generator, together with a CaWO4 crystal with an NTD-Ge glued
on, were installed in a 3He/4He dilution refrigerator. The calorimeter was cooled down to a temperature as low as 12 milli-Kelvin
while the PMT was operating and the energy of 122 keV gamma from a 57Co radioactive source was determined with an energy
resolution of 20% (FWHM) via scintillation photons, detected by the low-temperature PMT. This detector technique is especially
attractive for scaling up cryogenic dark matter detectors or neutrinoless double beta decay experiments.
Name: Tim Linden
University: The Ohio State University
Abstract title: Multiwavelength Observations Shed Light on the Galactic Center Gamma-Ray Excess
Abstract: Observations over the last several years have clearly detected a bright gamma-ray excess emanating
from the center of the Milky Way Galaxy. However, the source of this excess remains unclear. Explanations
including dark matter annihilation, a population of millisecond pulsars, outbursts from Sgr A*, and diffuse
gamma-ray mismodeling, produce reasonable fits to the gamma-ray data. In this talk, I will show how multi-wavelength
observations can be utilized to break these degeneracies, and differentiate between astrophysical and dark matter
explanations for the gamma-ray data.
Name: C. J. Martoff
University: Temple University for DarkSide Collaboration
Abstract title: Proposed DarkSide-20k Liquid Argon Dark Matter Search
Abstract: DarkSide-20k is a dual-phase liquid argon TPC with 23 tons active mass, now being proposed to INFN and U.S.
agencies. The experiment is based on technologies operationally proven in DarkSide-50 (underground argon,
ultra-stable cryogenics) as well as new technology for light detection (SiPM's) and construction techniques.
The extraordinary pulse-shape background rejection power of the LAr-TPC technique, along with the use of
underground argon having less than a thousandth the 39-Ar background of atmospheric argon, will allow
DarkSide-20K to reach a background-free exposure of 100 t yr in a five-year run. The corresponding
WIMP-nucleon cross section sensitivity is 1 x 10^{-47} cm^2 at 1 TeV/c^2 WIMP mass. This talk will
describe the planned configuration, technology and performance of DarkSide-20k.
Name: Reina Maruyama
University: Yale University
Abstract title: Results from the DM-Ice17 Dark Matter Experiment at the South Pole
Astrophysical observations give overwhelming evidence for the existence of dark matter. DAMA collaboration's
observation of dark matter-induced annual modulation signal has not yet been confirmed. I will describe
DM-Ice, a low-background NaI(Tl)-based dark matter experiment aimed at understanding the DAMA signal and
unambiguously testing the hypothesis of a dark-matter induced annual modulation signal. DM-Ice17, a
prototype experiment consisting of 17kg of NaI(Tl) detectors, has been continuously operating at the
South Pole for over 4 years demonstrating the feasibility of a low-background experiment in the
Antarctic ice. The results from DM-Ice17 and prospects for DM-Ice will be presented.
Name: Maria Elena Monzani
University: SLAC National Accelerator Laboratory
Abstract title: Expected Background in the LZ Experiment
Abstract: The LZ experiment, featuring a 7-tonne active liquid xenon target, is aimed at achieving unprecedented
sensitivity to WIMPs with the background expected to be dominated by astrophysical neutrinos. To reach this goal,
extensive simulations are carried out to accurately calculate the electron recoil and nuclear recoil rates in the
detector. Both internal (from target material) and external (from detector components and surrounding environment)
backgrounds are considered. A very efficient suppression of background rate is achieved with an outer liquid
scintillator veto, liquid xenon skin and fiducialisation. Based on the current measurements of radioactivity
for different materials, it is shown that LZ can achieve the reduction of a total background for a WIMP search
down to about 2 events in 1000 live days for 5.6 tonne fiducial mass.
Brian D. Nord
University: FNAL
Abstract title: Early results from the Dark Energy Survey
Abstract: The expansion of the universe is accelerating, a discovery that earned the 2011 Nobel Prize in physics.
Constraining the evolution of dark energy is the primary goal of the Dark Energy Survey (DES). After achieving
first light in 2012, followed by a few months of commissioning and science verification, DES is about to complete
its third season of science observations at the Blanco 4-meter telescope at the Cerro Tololo Inter-American
Observatory in Chile. The DES Collaboration built a new 570-megapixel digital imager, the Dark Energy Camera
(DECam), to carry out a deep, wide survey over the course of five (5) years---observing thousands of Type-Ia
supernovae and hundreds of millions of galaxies. The thick, red-sensitive imager will allow us to see more
supernovae and galaxies at higher redshift than previous surveys, like the Sloan Digital Sky Survey (SDSS).
These observations will provide a suite of cosmological signatures: the supernova Hubble diagram, galaxy
cluster number counts, large-scale galaxy clustering and gravitational lensing. With this data, we will
probe both the cosmic expansion history and the growth of large-scale structures, and thus explore the
nature of dark energy. I will describe DES and early results, including strong lens discoveries, galaxy
cluster catalogs, dark matter maps and preliminary cosmological constraints from weak lensing shear.
Name: Christian Regenfus
University: CERN
Abstract title: ArDM-1t
Abstract: The ArDM experiment, the first ton-scale Liquid Argon detector for direct Dark Matter searches, was
commissioned at full target size in 2015. The performance of the entire installation was confirmed in a 6 month
long physics data run in single phase operational mode. The results give an exciting perspective for the planned
double phase operation of ArDM in 2016. In addition, the ArDM experimental program was recently extended in
respect of developments towards next generation LAr DM experiments of multi tens of ton size.
Name: Florian Reindl
University: Max Planck Institute for Physics Munich
Abstract: Today, direct dark matter searches apply a great variety of different detector technologies, all
aiming to observe dark matter particles interacting in their detectors. Thereby cryogenic experiments
currently provide the best sensitivity for light dark matter particles, with the CaWO4-based CRESST-II
experiment advancing to the sub-GeV/c^2 dark matter particle mass regime. In this contribution we will
present results from the last measurement campaign which was finished in August 2015, after more than
two years of data taking. Currently, CRESST-III is on its way, featuring detectors consequently optimized
for the measurement of very small energy deposits to further explore the low-mass region. We will
report on the status of the experiment and give an outlook on the anticipated sensitivity of the CRESST
dark matter search.
Name: Biagio Rossi
University: Princeton University
Abstract title: SiPM for DarkSide-20k
Abstract: One of the crucial problems to be faced for the development of large size (multi ton-scale)
liquid argon experiments is the lack of reliable and low background cryogenic PMTs due to their intrinsic
radioactivity, cost, and borderline performance at 87 K. This rules rule them out as a possible candidates
for photosensors for multi-ton detectors. The DarkSide Collaboration initiated an R&D effort to employ
large arrays of Silicon Photomultiplier (SiPM) coupled to custom cryogenic front-end electronics which
would replace the cryogenic PMTs used in the DarkSide-50 detector. The very encouraging results obtained
so far will be presented as well as the R&D plan towards DarkSide-20k.
Name: Paul Scovell
University: University of Oxford
Abstract title: Materials screening for the LZ experiment
Abstract: When constructed, the LZ experiment will represent the most sensitive dark matter detector to date. In
order to reach this sensitivity, the selection of materials used in construction is of paramount importance. The
LZ collaboration has developed a wide ranging suite of materials screening instruments in both the US and the UK
to characterize the intrinsic radioactivity of all components that will be used in the experiment. This assay
program includes screening for both fixed (U,Th,K) and mobile (Rn) contaminants in materials. It is through the
variety of techniques used and the number of instruments available that we will be able to fully understand and
minimise the radioactive backgrounds from materials in LZ. This talk will give an overview of the LZ screening
facilities and will discuss recent assay results of some of the larger items (including the identification of
the lowest background titanium assayed to date) that will be used in the construction of the LZ experiment.
Name: Marco Selvi
University: INFN Bologna
Abstract title: Sensitivity Projections for XENON1T
Abstract: We present the XENON1T expected sensitivity to the spin-independent WIMP-nucleon interaction cross section,
based on Monte Carlo predictions of the electronic and nuclear recoil backgrounds. The total electronic recoil background
in 1 tonne fiducial volume and (1, 12) keV electronic recoil equivalent energy region, before applying any selection to
discriminate between electronic and nuclear recoils, is (1.80±0.15)⋅10−4 (kg⋅day⋅keV)−1, mainly due to the decay of 222Rn
daughters inside the xenon target. The nuclear recoil background in the corresponding nuclear recoil equivalent energy
region (4, 50) keV, is composed of (0.6±0.1) (t⋅y)−1 from radiogenic neutrons, (1.8±0.3)⋅10−2 (t⋅y)−1 from coherent
scattering of neutrinos, and less than 0.01 (t⋅y)−1 from muon-induced neutrons. The sensitivity of XENON1T is calculated
with the Profile Likelihood Ratio method, after converting the deposited energy of electronic and nuclear recoils into
the scintillation and ionization signals seen in the detector. We take into account the systematic uncertainties on
the photon and electron emission model, and on the estimation of the backgrounds, treated as nuisance parameters.
The main contribution comes from the relative scintillation efficiency Leff, which affects both the signal from WIMPs
and the nuclear recoil backgrounds. After a 2 y measurement in 1 t fiducial volume, the sensitivity reaches a minimum
cross section of 1.6⋅10−47 cm2 at mχ=50 GeV/c2.
University: Hokkai-Gakuen University
Abstract title: Singlet doublet mixed complex scalar dark matter
Abstract: We study the property of a sInglet-doublet mixed complex scalar particle as a dark matter candidate. We find viable parameter region where this model is consistent with the various current experimental constraints. We also discuss the detection prospect in future experiments.
Name: Tom Shutt
University: SLAC
Abstract: I will report on the status of the LZ dark matter experiment. LZ will be located at SURF in the
former Homestake mine in South Dakota, and features a 7 ton liquid Xe TPC with a 5.6 ton fiducial volume.
The spin-independent WIMP sensitivity is estimated as 2e-48 cm^2 at 50 GeV WIMP mass. This talk will describe
the design, status, and science reach of the experiment.
Name: Dr Peter F Smith
University: Department of Physics and Astronomy, UCLA
Abstract title: Possibilities for terrestrial experiments to detect keV sterile neutrinos, Peter F Smith (Department
of Physics and Astronomy, UCLA)
Abstract: In 1999 X Shi and G M Fuller predicted that kev mass sterile neutrinos would provide a plausible candidate
for the Galactic Dark Matter. Recently an unidentified 3.6 keV X-ray signal, from both galaxy clusters and our
galactic centre, has been reported and could be the result of rare decays of 7.2 keV sterile neutrinos forming all
or part of the non-luminous matter, with a relative coupling ~ 1E-10. Direct detection as a component of the dark
matter in our galaxy would be possible by inverse beta decay, but large quantities of target radio-isotopes would
be needed, in ultra thin layers. Direct production and detection in the laboratory is possible either by distortion
of the electron spectrum in beta decay, or as rare individual events by four-momentum reconstruction of beta decay
or K-capture events. Some challenging design problems for the latter will be outlined.
Name: Daniel Snowden-Ifft
University: Occidental College
Abstract title: DRIFT Results
Abstract: The Directional Recoil Identification from Tracks (DRIFT) collaboration has been running background free
for over a year. The latest directional limits will be presented as well as evidence for the detection of ambient
neutrons from unshielded running. Future plans will also be discussed.
Name: Peter Sorensen
University: LBL
Abstract title: Limitations and applicability of the Lindhard model for few keV nuclear recoils
Abstract: Many direct dark matter searches either rely on or benefit from detection of electronic signals. Direct
calibration of electronic signal yields from neutron scattering, as a proxy for dark matter induced nuclear
recoils, remains difficult. The smallest detectable nuclear recoil energies are in the few keV regime for many
detectors, and due to A^2 coherence enhancements, the scattering rate is predicted to increase with decreasing
energy. The widely used Lindhard model of quenching is widely understood to be inapplicable in this low-energy
regime. The understanding is not quite correct. In this talk I will discuss the successes and limitations of the
Lindhard model for homogenous targets. Specific attention will be given to low-energy limitations, applicability
to liquid noble gases and kinematic cutoff of signal production.
Name: Burkhant Suerfu
University: Princeton University
Abstract title: Status of the SABRE NaI(Tl) Dark Matter Experiment
Abstract: SABRE is an experiment that is being developed to search for dark matter with an array of NaI(Tl)
scintillating crystals. A primary goal is to test the DAMA-LIBRA modulation signal claimed to be evidence
for dark matter. The experiment will employ NaI(Tl) crystals with low levels of internal radioactivity in
an active shield of liquid scintillator and water. SABRE has produced large NaI(Tl) crystals with radio-purity
levels comparable to that of DAMA-LIBRA, and research toward higher radio-purity is ongoing. One detector
will be deployed in the LNGS underground laboratory in Italy. A second detector will be located in Australia
in the Stawell Underground Physics Laboratory, 240 km west of Melbourne. An overview of the detector design
will be presented, together with a report on progress toward low radioactivity NaI(Tl) crystals.
Name: Javier Tiffenberg
University: Fermilab
Abstract: The DAMIC detector, currently taking data at Snolab, is a Dark Matter search experiment that
employs scientific grade CCDs made of silicon as target material. The low readout noise of the CCDs
yield to a ionization energy threshold below 60 eVee and provides optimal sensitivity for low mass
WIMPs (< 20 GeV). The pixelization (15 microns) and superb energy resolution of the detectors allow
for unique background rejection and identification techniques. We present here an overview of the
DAMIC experiment together with a summary of the latest results produced using data acquired at Snolab
since its installation in December 2012. We also discuss the commissioning schedule and reach of
DAMIC100, a 100 g silicon target detector currently being installed at SNOLAB.
Name: Virginia Trimble
University: Univ. of California Irvine & Queen Jadwiga Observatory
Abstract title: LOST IN THE DARK: A Protohistory of Dark Matter
The Greeks were probably not the first to think of everything, but they were quite often the first to write about it.
Thus the first dark matter candidate was the counter-earth of Philolaus (c. 460 BCE), with its illuminated face forever
turned away from us. The eclipsing binary interpretation of Algol brought forward the idea (Piggott & Goodricke
1780's) of stars not yet lit up, while the incorporation of thermodynamics into the astronomical tool kit suggested
dark, dead stars. Jeans found a local number density for these (about 3 times the number of illuminated stars) in
1922, the same year that Kapteyn set a comparable limit to what he called dark matter. The phrase appears as an
index item in Russell et al's 1927 "Astronomy" and cannot, therefore, have been invented any later.
The first extragalactic estimate came from Lundmark (writing in German in the Meddelande of the Lund Observatory
in 1930). One of the columns of his Tabelle 4 is headed (Leuchtende + dunkle Materie)/(Leudchtende Materie) and
gives values from 6 to 100 for six galaxies, including 20 for Andromedanebel and 30 for NGC 4595. Binary galaxies
belonged to Holmberg (1937), the Virgo cluster to Sinclair Smith (1936), flat rotation curves to Babcock (1939, M31)
and Oort (1940 NGC 3115). Then there was a war, but by the time of a 1961 Symposium in Santa Barbara, focussed on
the large velocity dispersions of clusters of galaxies, the votes for dark matter slightly outnumbered those for
unbound clusters and other alternatives. A constant of gravity increasing with distance came a smidge later
(Arigo Finzi 1963). The tipping point was arguably 1974 with a pair of short papers summarizing M/L ratios vs.
distance scale (which could of course have been plotted before WWII). I mention only the slightly earlier
and much less often cited Einasto, Kaasik, & Saar (published in Nature, in case you are thinking of more
Lund Meddelande), because they make clearer that they were advocating a new component of the Universe.
Please do not doubt my enormous respect and affection for Fritz Zwicky and Vera Rubin, but the published
papers are as they are.
Name: Philip von Doetinchem
University: University of Hawaii at Manoa
Abstract title: Cosmic-ray antideuteron searches
Abstract: Recent years have seen increased theoretical and experimental effort towards the first-ever detection
of cosmic-ray antideuterons, in particular as an indirect signature of dark matter annihilation or decay. In
contrast to indirect dark matter searches using positrons, antiprotons, or gamma-rays, which suffer from relatively
high and uncertain astrophysical backgrounds, searches with antideuterons benefit from very suppressed conventional
backgrounds, offering a potential breakthrough in unexplored phase space for dark matter. The presentation will
review dark matter theories that can be probed with antideuterons, the challenges to predictions and interpretations
of antideuteron signals, and the experimental efforts toward cosmic antideuteron detection.
Name: Samuel Witte
University: UCLA
Abstract title: Potential Target Dependence of the Annual Modulation in Direct Dark Matter Experiments
Abstract: It is widely believed that the annual modulation of the rate in direct detection experiments is common to all
experiments. In this talk I will show that this is not necessarily the case. The gravitational focusing of dark matter
particles by the Sun already modifies this picture by e.g. making the phase of the annual modulation dependent on the
recoil energy. Moreover, should the scattering cross section contain a nonfactorizable target and velocity dependence,
the annual modulation observed by experiments employing different target materials could differ markedly. As an example,
I will explicitly show how the time of maximum of the rate varies for magnetic dark matter scattering off fluorine,
sodium, germanium, iodine, and xenon.
Name: Hai-Bo Yu
University: UC Riverside
Abstract title: The Self-Interacting Dark Matter Paradigm
Abstract: Astrophysical observations spanning dwarf galaxies to galaxy clusters indicate that dark matter halos are less
dense in their central regions compared to expectations from collisionless dark matter N-body simulations. Using detailed
fits to dark matter halos of galaxies and clusters, we show that self-interacting dark matter may provide a consistent
solution to the dark matter deficit problem across all scales, even though individual systems exhibit a wide diversity in
halo properties.
name: Qian Yue
University: Tsinghua University, Beijing
Abstract title: China Jinping Underground Laboratory and potential experiments in CJPL-II
Abstract: China Jinping Underground Laboratory (CJPL) is located in a traffic tunnel with about 2400 m of rock overburden
and low ambient radioactivity background. CJPL was constructed by Tsinghua University and Yalong River Hydropower Development
Company and inaugurated on Dec. 12, 2010. The Phase-I laboratory (CJPL-I) has about 4000 m3 of space. The important parameters
such as muon flux and neutron flux have been measured. The CJPL Phase-II with large space has been constructed from 2015 on
and will be ready for low background experiment in 2016. Now there are two dark matter experiments: CDEX and PandaX run their
detectors in CJPL-I. Several new proposals for dark matter, double beta decay experiments, and neutrino experiments will plan
to use the new spaces at CJPL-II. My report will give more information about the new plans.