Conveners
Dark Matter
- Benjamin Safdi
- Lindley Winslow (Massachusetts Institute of Technology)
- Rupak Mahapatra (Texas A&M University)
Dark Matter
- Lindley Winslow (Massachusetts Institute of Technology)
- Rupak Mahapatra (Texas A&M University)
- Benjamin Safdi
Dark Matter
- Lindley Winslow (Massachusetts Institute of Technology)
- Benjamin Safdi
- Rupak Mahapatra (Texas A&M University)
Dark Matter
- Lindley Winslow (Massachusetts Institute of Technology)
- Rupak Mahapatra (Texas A&M University)
- Benjamin Safdi
Dark Matter
- Rupak Mahapatra (Texas A&M University)
- Lindley Winslow (Massachusetts Institute of Technology)
- Benjamin Safdi
Dark Matter
- Benjamin Safdi
- Lindley Winslow (Massachusetts Institute of Technology)
- Rupak Mahapatra (Texas A&M University)
Dark Matter
- Benjamin Safdi
- Rupak Mahapatra (Texas A&M University)
- Lindley Winslow (Massachusetts Institute of Technology)
Dark Matter
- Lindley Winslow (Massachusetts Institute of Technology)
- Benjamin Safdi
- Rupak Mahapatra (Texas A&M University)
Description
parallel sessions
The couplings of the Standard Model sector to the scale invariant degrees of freedom can open the possibility to study the hypothesized particles called as dark photons (DP). The latter are associated with dark matter, neutralinos and others. The model for the DP particle solvable in 4-dimensional space-time is studied at the lowest order of perturbative theory using canonical quantization....
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable...
The flagship LHC experiments are arranged radially outward from the proton interaction point, but dark matter mediators and other new light particles could be produced in a collimated beam by meson decays along the beam axis, and escape detection. FASER (ForwArd Search ExpeRiment) will explore this “blind spot” for the first time. The experiment will be sited 480 meters from the ATLAS...
The PADME experiment, at the Laboratori Nazionali di Frascati of INFN, is a fixed-target, missing-mass experiment designed to search for a dark photon (A’), the hypothetical gauge boson of a new U(1) symmetry in a hidden sector of particles neutral under Standard Model interactions. The design performance of the experimental apparatus allows the investigation of A’ mass ranges up to 23.7 MeV...
The Heavy Photon Search experiment searches for an electro-produced dark photon using an electron beam provided by the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility. HPS has successfully completed two engineering runs. In 2015 using a 1.056 GeV, 50 nA electron beam, 1.7 days (10 mC) of data was obtained and 5.4 days (92.5 mC) of data was collected in 2016 using a 2.3...
We are in an age of large precision astrometric datasets, most recently thanks to ESA's Gaia mission, which has already measured the full 6-dimensional phase space of over 7 million stars. One of the many exciting physics outcomes of Gaia is the ability to measure the Milky Way's gravitational potential, as inferred from stellar kinematics. This can be leveraged to make precise statements...
We study how the void environment affects the formation and evolution of
galaxies in the universe by comparing the ratio of dark matter halo mass to
stellar mass of galaxies in voids with galaxies in denser regions. Using
spectroscopic observations from the SDSS MaNGA DR 15, we estimate the dark
matter halo mass of \Nvoid void galaxies and \Nwall galaxies in denser regions.
We...
If dark matter has strong self-interactions, future astrophysical and cosmological observations, together with a clearer understanding of baryonic feedback effects, might be used to extract the velocity dependence of the dark matter scattering rate. To interpret such data, we should understand what predictions for this quantity are made by various models of the underlying particle nature of...
We show that a simple Higgs-portal dark matter model can contain stable non-topological soliton states of dark matter. This macroscopic dark matter candidate has its interior in an electroweak symmetry unbroken vacuum. They can have its radius around the atomic scale and mass as large as $10^{26}$ GeV. We discuss the formation of these dark matter balls from the first order electroweak phase...
We show how a simple dissipative dark sector can form exotic compact objects that vary in size from a few to millions of solar masses. These exotic compact objects may be detected and their properties measured at new high-precision astronomical observatories, giving insight into the particle nature of the dark sector without the requirement of non-gravitational interactions with the visible sector.
I present a new public Python package, DarkHistory, for computing the effects of dark matter annihilation and decay on the temperature and ionization history of the early universe. DarkHistory, which is fast, convenient, and easy to use, simultaneously solves for the evolution of the free electron fraction and gas temperature, and for the cooling of annihilation/decay products and the...
If a component of dark matter is millicharged, dark matter-baryon scattering can induce large effects in the 21-cm global signal by cooling the baryons. This can be achieved without being excluded by other cosmological, astrophysical or terrestrial constraints. We point out two important effects which have been overlooked in previous analyses. First, introducing a dark interaction between the...
X-ray observations of clusters and galaxies have detected an unexplained X-ray emission line around 3.5 keV. This line has been the subject of many recent works due to its potential explanation as a product of decaying dark matter. I discuss recent work in which we exploit the fact that the Milky Way halo is as bright in dark matter decay as previous targets but has significantly reduced...
The General Antiparticle Spectrometer (GAPS) is a balloon-borne experiment designed to identify cosmic antinuclei, in particular antideuterons from dark matter annihilation or decay, using the uniquely characterized atomic X-rays and charged particles from the decay of exotic atoms. With such a novel detection approach, benefitting from a custom-developed large-area silicon tracker and a...
A keV-scale sterile neutrino is a popular candidate for dark matter, with a decay signature of a mono-energetic photon that can be probed using X-ray telescopes. The NuSTAR X-ray observatory's wide-angle aperture for unfocused X-rays has allowed it to set world-leading limits on the decay rate of sterile neutrinos with masses 10-50 keV. I will present our constraints on the flux of new X-ray...
Dark sector models with light or massless mediators naturally introduce elastic and dissipative self-interactions of dark matter. The heat exchange induced by the elastic scattering permits the gravothermal evolution of the halo. Through the evolution, a halo with a cuspy inner density profile develops a core first but become cuspy again at late time. We find that a mild dissipative scattering...
Milky Way dwarf spheroidal galaxies (dSphs) provide well-known challenges to the standard cold and collisionless dark matter (CDM) paradigm in relation to well-known puzzles as the too-big-to-fail problem. At the same time, the self-interacting dark matter (SIDM) scenario offers a promising solution to the putative small-scale crisis, while inheriting all the successes of CDM at large scales....
DarkSide uses a dual-phase Liquid Argon Time Projection Chamber to search for WIMP dark matter. The talk will present the latest result on the search for low mass ($M_{WIMP} <20GeV/c^2$ ) and high mass ($M_{WIMP}>100GeV/c^2$) WIMPs from the current experiment, DarkSide-50, running since mid 2015 a 50-kg-active-mass TPC, filled with argon from an underground source. The next stage of the...
LUX (Large Underground Xenon) was a dark matter experiment using a two-phase Xe Time Projection Chamber housed and operated at the Sanford Underground Research Facility (SURF) in Lead, South Dakota from 2012 to late 2016. It previously published three world-leading limits on the spin-independent cross-section for Weakly Interacting Massive Particle (WIMP) dark matter via direct detection, with...
The LUX-ZEPLIN (LZ) Dark Matter Collaboration aims to identify the elusive dark matter particle that appears to make up one quarter of the energy density of our universe. LZ is optimized to detect dark matter that produce nuclear recoils using a multi-tonne liquid xenon target, making it critical that all nuclear recoil background events are identified and understood. We present here simulated...
Dark Matter makes up ~25% of the energy density of the universe but has yet to be directly detected. Numerous efforts are ongoing to build ever bigger and ever more sensitive detectors to try and detect it. The LUX-ZEPLIN (LZ) experiment, with its 10 tons of liquid xenon, will reach unprecedented sensitivity. However, this can only happen if all potential backgrounds are under control. To make...
This talk will present the science case for a future generation-3 liquid xenon time projection chamber for astroparticle physics. Such an experiment is envisioned to follow the current generation of experiments such as LZ and XENONnT, delivering diverse science at moderate cost. With a sensitivity sufficient to probe WIMP dark matter down to the signal from atmospheric neutrinos, numerous...
The SuperCDMS SNOLAB experiment will search for low-mass (< 10 GeV/c^2) dark matter employing germanium and silicon crystals instrumented with cryogenic phonon and ionization detectors. The expected dominant backgrounds are due to long-lived radioactive isotopes present and/or produced in the natural environment. Specifically, Si-32 is cosmogenically created in the atmosphere and is...
The DAMIC experiment at SNOLAB uses thick fully-depleted scientific grade charge-coupled devices (CCDs) to search for the interactions of dark matter particles in the galactic halo with ordinary silicon atoms. Because of the low instrumental (less than $2\ e^-$) noise, DAMIC CCDs are particularly sensitive to ionization signals expected from low-mass dark matter particles. For the past two...
Axions, which can solve the Strong CP problem, and axion-like particles (ALPs), which arise naturally in many models of high-scale physics, provide theoretically compelling dark matter candidates. Axions and ALPs which couple to photons have been shown to produce observable radio emission through their conversion to photons in the magnetospheres of neutron stars, providing a means of indirect...
The Axion Dark Matter Experiment (ADMX) is seeking to discover the axion particle as both a solution to the strong-CP puzzle of QCD and to the nature of dark matter. The apparatus consists of a frequency tune-able resonant microwave cavity immersed in a strong mechanical field at sub Kelvin temperatures and read out by quantum amplifiers. Recent results and future prospects at a sensitivity...
The axion is a hypothetical particle proposed to solve the strong $CP$ problem, and also a candidate for dark matter. This non-relativistic particle in the galactic halo can be converted into a photon under a strong magnetic field and detected with a microwave resonant cavity. Relying on this detection method, many experiments have excluded some mass regions with certain sensitivities in terms...
The evidence for the existence of Dark Matter is well supported by many cosmological observations. Separately, long standing problems within the Standard Model point to new weakly interacting particles to help explain away unnatural fine-tunings. The axion was originally proposed to explain the Strong-CP problem, but was subsequently shown to be a strong candidate for explaining the Dark...
The presence of dark matter provides some of the most tangible evidence for the existence of physics beyond the Standard Model. One compelling dark matter candidate is the axion, a light boson that was originally postulated as a solution to another outstanding issue, the strong CP problem in QCD. ABRACADABRA is an experimental program to search for sub-$\mu$eV axion and axion-like dark...
We report on a laboratory-scale experiment searching for axion-like dark matter in the mass range from about 50 peV to several neV. The electromagnetic interaction between a background axion-like field and the azimuthal magnetization of a ferromagnetic toroid creates an oscillating axial magnetic field. We use SQUID magnetometers to search for this field. The apparatus is placed inside a...
Cosmic Axion Spin Precession Experiment (CASPEr) is a laboratory scale search for the nature of dark matter. CASPEr searches for the axion and axion-like-particles (ALPs) as dark matter candidate in the mass range of a few feV to $\mu$eV [D. F. Jackson Kimball, et al., arXiv:1711.08999]. CASPEr uses experimental techniques based on Nuclear Magnetic Resonance (NMR) and precision magnetometry....
Cosmic Axion Spin Precession Experiment (CASPER) is a laboratory scale experiment looking for axion dark matter, using nuclear magnetic resonance (NMR) techniques. Dynamic nuclear polarization (DNP) can be used to improve experimental sensitivity. I will present first results from electron paramagnetic resonance experiments on transient light-induced paramagnetic centers in ferroelectric...
In recent years, the development of fast and low-dark-count single-photon detectors for photonic quantum information applications promise a radical improvement in our capacity to search for dark matter. The advent of superconducting nanowire detectors, which have fewer than 10 dark counts per day and have demonstrated sensitivity from the mid-infrared to the ultraviolet wavelength band,...
A spontaneously broken hidden U(1)$_h$ gauge symmetry can explain both the dark matter stability and the observed relic abundance. In this framework, the light gauge boson can mediate the strong dark matter self-interaction, which addresses astrophysical observations that are hard to explain in collisionless cold dark matter. Motivated by flavoured grand unified theories, we introduce...
We present a new class of direct detection signals; absorption of fermionic dark matter. We enumerate the operators through dimension six which lead to fermionic absorption, study their direct detection prospects, and summarize additional constraints on their suppression scale. Such dark matter is inherently unstable as there is no symmetry which prevents dark matter decays. Nevertheless, we...
An extension of the Standard Model gauge symmetry by the gauge group $U(1)_{T3R}$ is proposed in order to understand the Yukawa coupling hierarchy in the SM. Only the right-handed fermions of the first two generations are charged under the $U(1)_{T3R}$. In addition to the new dark gauge boson, a dark scalar particle acquires a vacuum expectation value (vev) which breaks the $U(1)_{T3R}$...
We present direct detection constraints on sub-GeV dark matter interacting with electrons using the DAMIC@Snolab experiment – which utilizes high resistivity, scientific grade CCDs to image ionization deposits produced by particle interactions within the devices. Using a relatively novel methodology of placing constraints based on leakage current, we report preliminary limits probing new...
The cloud and bubble chambers have historically been used for particle detection, capitalizing on supersaturation and superheating respectively. We present now on the snowball chamber, which utilizes a supercooled liquid. In our prototypes, an incoming particle triggers crystallization of purified water. We demonstrate that water is supercooled for a significantly shorter time with respect to...
HeRALD, the Helium Roton Apparatus for Light Dark Matter, will use a superfluid helium target to study the sub-GeV dark matter parameter space. The HeRALD design is sensitive to all signal channels produced by nuclear recoils in superfluid helium: singlet and triplet excimers, as well as phonon and roton vibrational excitations. Excimers are detected via calorimetry in and around the...
Next generation liquid xenon TPCs, like LZ, will offer an order of magnitude improvement in sensitivity to WIMP dark matter with masses above 10 GeV. The introduction of a low-Z element, like hydrogen, into a large xenon TPC would take advantage of the excellent self-shielding xenon environment, while potentially extending sensitivity down to ~50 MeV WIMP masses. This talk will describe...
The LBECA collaboration plans to optimize xenon time projection chamber (TPC) sensitivity to sub-GeV dark matter by focusing on few-electron ionization signals. Previous experiments such as XENON1T and LUX have observed an increase in few-electron backgrounds up to 100s of milliseconds after energetic particle interactions, which limits their sensitivity to such low-energy interactions. The...
Analyses of the latest Gaia data release (DR2) by various groups have revealed that the dark matter (DM) halo around the solar neighborhood is in disequilibrium, and an O(1) fraction of the DM may have been accreted during recent dwarf galaxy mergers. These results indicate a departure from the Standard Halo Model (SHM) of DM velocity distribution, which could significantly affect DM signals...
The Non-Relativistic Effective Field Theory (NREFT) provides an economic parametrization of different possible interactions between dark matter (DM) and the target nucleus that could be probed by direct detection. We consider a diverse set of Galilean-invariant NREFT operators with different spin, momentum and velocity dependence, for both light and heavy mediators, and investigate the effect...
The non-detection of GeV-scale WIMPs has led to increased interest in more general candidates, including sub-GeV dark matter. Direct detection experiments, despite their high sensitivity to WIMPs, are nominally blind to dark matter much lighter than $\sim1$ GeV. Recent work has shown that cosmic rays scattering with sub-GeV dark matter would both alter the observed cosmic ray spectra and...
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable...
