Cosmology has advanced from "2.5 facts" in 1963 to a very data-rich
field today. This has led to the determination of the baryon
density, the dark matter density, and the dark energy density. But
more facts lead to a greater reliance on advanced statistical
techniques, which are usually useful but occasionally misleading.
It is important to consider "look elsewhere effects", and to...
Twenty years after the discovery of cosmic acceleration, or Dark Energy, there is now robust evidence from a number of independent precision measurements. I will review recent progress on determining the properties of Dark Energy from different cosmological probes, highlight growing tensions in the LCDM paradigm, and conclude with an outlook on upcoming large experiments of the early 2020s.
Immense progress has been made in the last decade in simulating and understanding the role that baryons have in influencing the evolution and structure of dark matter on small scales and in dwarf galaxies. In this talk I will review the successes in modeling small scales and discuss the implications for interpreting the dark matter model. I will also highlight some remaining challenges and...
The results of the Gaia astrometric mission have ushered in a new era of "precision Galactic dynamics." Using this new phase-space map of Galactic stars with unprecedented volume, we are beginning to obtain new insights into the dark matter distribution in our Galaxy. Thanks to significant advances on the computational front, meanwhile, we can now compare these insights directly with, and test...
In the last decades an incredible amount of evidence for the existence of dark matter has been accumulating. At the same time, many efforts have been undertaken to try to identify what dark matter is.
Indirect searches look at places in the Universe where dark matter is known to be abundant and seek for possible annihilation or decay signatures. Indirect searches with the Fermi Gamma-ray...
Axions generically emerge in many contexts of particle physics. They may also solve long standing theoretical problems such as the strong CP, gauge hierarchy and the cosmological constant problems. In this talk, I will briefly discuss these theoretical ideas and focus on new experimental methods to find these particles
Electroweak singlets, sterile neutrinos, remain viable dark matter candidates. It is tantalizing that much remains mysterious about the physics of the neutrino sector. Luckily, neutrinos impact key issues in cosmology and compact objects, and new physics in this sector therefore may reveal itself. Moreover, the advent of new neutrino experiments, and planned next generation X-ray...
The generalization of dark matter to dark sectors, with potentially rich matter content and interactions, has opened up new avenues for detection. In particular, there are now many new motivations for light, long-lived particles, which can be probed by novel experiments at accelerators. I will review these motivations, describe of the interplay of theory and experiment in this area, and give...
Detection of a Dark Matter signal in an ultra-low background terrestrial detector will provide the most direct evidence of its existence and will represent a ground-breaking discovery in physics and cosmology. Among the variety of dark matter detectors, liquid xenon time projection chambers have shown to be the most sensitive, thanks to a combination of very large target mass, ultra-low...
Overview of direct dark matter experiments using argon as target.
We analyze the potential dark matter implications of LHC events with missing transverse momentum and a W′ resonance, decaying via tb̅ to a hadronic final state. This final state remains unexamined by LHC experiments, but contains significant new discovery potential. We introduce a benchmark model for production of a W′ boson in association with dark matter, propose reconstruction and...
Axion-like particles (ALPs) are a well-motivated candidate for constituting a significant fraction of cold dark matter in the Universe. They are hypothesized to be produced in high-energy environments, such as core-collapse supernovae (CCSNe), and could undergo conversion into gamma-rays in the presence of an external magnetic field, spectrally peaking at ~60 MeV. CCSNe are often invoked as...
Self-annihilating dark matter, captured in the gravitational field of stars or other compact objects, can produce detectable fluxes and impact the evolution and observability of Population III stars. In the regime between WIMP dark matter masses ($10^{2}$ GeV) and superheavy masses ($>10^{8}$ GeV), the number of scattering events required for capture increases from of order unity to thousands...
Self-interacting dark matter (SIDM) is promising to solve or at least mitigate small-scale problems of cold dark matter. Simulations have proven to be a powerful tool to study SIDM within the astrophysical context. However, it turned out to be difficult to model all dark matter models with high fidelity. Models with a differential cross-section very pointed into the forward direction, for...
The International Axion Observatory (IAXO) is a next-generation axion helioscope aiming at a sensitivity to the axion-photon coupling down to ~10$^{-12}$ GeV$^{-1}$, ~1.5 orders of magnitude beyond current helioscopes. IAXO will probe QCD axions in the 1 meV∼1 eV mass range, where they could constitute all or part of the dark matter in the Universe, as well as a large part of parameter space...
Among messengers used in indirect searches for dark matter (DM), neutrinos are special as they are neutral, light, and seldom interact. These unique properties give them advantages in astrophysical studies: they are advantageous over cosmic rays as they are able to point back to their sources and unlike gamma rays can exit environments of large matter and radiation densities. I will present a...
Searches for light (<1 GeV) dark matter are mainly limited by detector sensitivity to low energy deposits. Accurately characterizing dark matter detector thresholds calls for calibration sources that produce well-understood low energy neutron spectra and that are convenient to use. For low energy nuclear recoils, two existing strategies to produce monoenergetic neutrons are photoneutron...
We present the analysis of a sample of twenty-four galaxy-galaxy strong gravitational lens systems with a background source and deflectors from the Illustris-1 simulation. We create mock lensing observations with a data quality comparable to known samples such as the SLACS lenses, to study the degeneracy between the complex mass distribution of the lenses, subhaloes, the surface brightness...
For direct detection of sub-MeV dark matter, a promising strategy is to search for individual phonon excitations in a crystal. We perform an analytic calculation of the rate for light dark matter (keV < mDM < MeV) to produce two acoustic phonons through scattering in cubic crystals such as GaAs, Ge, Si and diamond. The multiphonon rate is always smaller than the rate to produce a single...
Primordial black holes are the only dark matter candidate that does not invoke a new elementary particle that survives to the present day, primordial black holes (PBHs) have garnered a lot of attention recently. Up to now, various observations have strongly constrained most of the mass range for PBHs, leaving only small ranges where PBHs could make up a substantial fraction of the dark matter....
I will review the status of cosmological searches for dark matter interactions, summarizing the best current limits on scattering of light particle candidates with protons derived from the cosmic-microwave-background anisotropy measurements. I will then present stringent new bounds on the same physics, inferred recently from the observed population of the Milky Way satellite galaxies. I will...
Strong gravitational lensing is one of the most accurate methods to measure the mass of galaxies and haloes and one of the most promising to investigate the nature of dark matter. Given that the abundance of small-mass and dark clumps is very different in cold and warm dark matter model, this kind of observations can put important constraints on the nature of dark matter, through the detection...
Gravitational lensing by galactic potentials is a powerful tool with which to probe the abundance of low-mass dark matter structures in the universe. Dark matter substructures or line-of-sight haloes introduce small scale perturbations to the smooth lensing potential. By observing detections (or non-detections) of such low-mass perturbers in lensed systems, we can place constraints on the halo...
Fermi-LAT has revolutionized our understanding of the gamma-ray sky from hundreds of MeV up to almost TeV energies. One of the main scientific goals of the LAT Team is to search for a dark matter production of gamma rays. This search is performed by analyzing the data in the direction of the most promising dark matter targets: the Galactic center, Milky Way Dwarf Spheroidal Galaxies, the...
An excess $\gamma$-ray signal toward the outer halo of M31 has recently been reported. Although other explanations are plausible, the possibility that it arises from dark matter (DM) is valid. In this talk I will first briefly review the Fermi-LAT observations toward the outer halo of M31. I will then present results for a DM interpretation of the observed excess. We use as our representative...
The Fermi-LAT collaboration has recently released a new point source catalog, referred to as 4FGL. For the first time, we perform a template fit using information from this new catalog and find that the Galactic center excess is still present. On the other hand, we find that a wavelet-based search for point sources is highly sensitive to the use of the 4FGL catalog: no excess of bright regions...
Persistent tension between low-redshift observations and the Cosmic Microwave Background radiation (CMB) suggests residual systematics or new physics beyond the standard LCDM model. Local observations of baryon acoustic oscillations with low-redshift distance calibrators can constrain the value of the Hubble constant and the sound horizon in a cosmologically independent way. When compared to...
As luminous tracers of the smallest observationally accessible dark matter halos, faint satellite galaxies orbiting the Milky Way (MW) have the potential to dramatically improve our understanding of dark matter microphysics. However, the confounding effects of baryonic physics on halo abundances and galaxy formation have made the interpretation of the observed MW satellite population unclear....
The clumpiness of dark matter on sub-kpc scales is highly sensitive to the tidal evolution and survival of subhaloes. In agreement with previous studies, we show that N-body realisations of cold dark matter subhaloes with centrally-divergent density cusps form artificial constant-density cores on the scale of the resolution limit of the simulation. These density cores drive the artificial...
In my talk, I will present new constraints on sterile neutrino mixing parameters obtained from both cosmological and direct measurements. For the first time, we model the sterile in a full 3+1 framework coupled to all other neutrino flavours and consistently calculate the cosmological perturbations. CMB data dominates the resulting constraints on mass splitting and the mixing matrix elements....
The Migdal Effect has seen a surge of interest in the last three years, particularly since Ibe et al (1707.07258) laid out the formalism for how to calculate an expected rate in a detector due to a dark matter signal. Multiple groups since then have expanded on this theoretical work to demonstrate the importance of such a signal in searching for sub-GeV dark matter, but all suffer from the...
We report on the status of WIMP dark matter by exploring the most invisible final state: neutrinos. We provide new model-independent limits on dark matter annihilation into neutrinos in a mass range spanning MeV to ZeV. Interestingly, our limits using the latest SuperK data are inching ever closer to the thermal relic cross section. We also show projections for the next generation of neutrino...
Many models of dark matter and hidden sectors predict new particles with masses below the electroweak scale. Low-energy electron-positron colliders such as BABAR are ideally suited to discover these hidden-sector particles. We present several recent BABAR searches for low-mass hidden-sector particles, including new searches for prompt and long-lived leptonically decaying hidden scalars...
I will review the variety of dark matter production models for sterile neutrino dark matter and their connection to structure formation and X-ray line detection, including the candidate 3.5 keV line. Structure formation continues to constrain dark matter to be increasingly cold, yet puzzles remain in galactic substructure. A few searches have claimed constraints on the presence of a dark...
The KATRIN (Karlsruhe Tritium Neutrino) experiment investigates the energetic endpoint of the tritium beta-decay spectrum to determine the effective mass of the electron anti-neutrino. The collaboration reported its first result in fall 2019, publishing the best limit up-to-date on neutrino mass from direct measurement.
The TRISTAN project aims at detecting a keV-sterile neutrino signature...
The HUNTER experiment (Heavy Unseen Neutrinos from Total Energy-Momentum) is a laboratory-based search for sterile neutrinos with sensitivity to the 20-280 keV mass range. The sterile neutrino mass will be reconstructed through precise measurement of the energy and momentum of the products in an electron capture decay of 131-Cs to determine the "missing" mass. Two reaction-microscope...
In this talk I will review the present status of supersymmetric dark matter candidates for 2020, in light of recent LHC and wimp direct detection limits.
Naturalness in the EW sector implies higgsino-like LSPs which are thermally underproduced while naturalness in the QCD sector seems to require the axion.
In fact, SUSY helps solve a major problem for axions: it can generate the needed...
We perform global fits on various SUSY models as well as on simplified DM models with leptophobic/philic mediators. These fits take into account astrophysical data (relic abundance and DD limits), searches at the LHC as well as other measurements (Higgs, low-energy and flavor observables). Based on these fits we predict the favored ranges for DM masses and Direct Detection cross sections. In...
We have extended the nonrelativistic effective theory of WIMP-nucleus scattering from WIMPs of spin 0, 1/2, and 1 to WIMPs of arbitrary spin, under the assumption of one-nucleon operators. New effective operators arise at each additional half-unit of WIMP spin. The nuclear structure functions are the same for WIMPs of all spin. The theory can easily include mediators of any mass, and form...
We proposed a mechanism called axiogenesis to explain the observed cosmological excess of matter over antimatter. A rotation of the QCD axion is induced by explicit Peccei-Quinn symmetry breaking in the early universe. The rotation corresponds to the asymmetry of the PQ charge, which is converted into the baryon asymmetry via QCD and electroweak sphaleron transitions. Such a rotation also...
The QCD axion is one of the most appealing candidates for the dark matter in the Universe. In this talk, I will discuss the possibility to predict the axion mass in the context of renormalizable grand unified theories where the Peccei-Quinn scale is determined by the unification scale. In the minimal theory with the KSVZ mechanism the axion mass is predicted to be in the range m = (3 - 13)...
If the length scale of possible extra dimensions is large enough, the effective Planck scale is lowered such that microscopic black holes could be produced in collisions of high-energy particles at colliders. These black holes evaporate through Hawking radiation of a handful of energetic particles drawn from the set of all kinematically and thermally allowed degrees of freedom, including dark...
Direct detection experiments have set increasingly stringent limits on the cross section for spin-independent dark matter-nucleon interactions. In obtaining such limits, experiments primarily assume the standard halo model (SHM) as the distribution of dark matter in our Milky Way. Three astrophysical parameters are required to define the SHM: the local dark matter escape velocity, the local...
Millicharged dark matter (mDM) would form a plasma and interact with the interstellar medium and electromagnetic fields within galaxies. In this presentation, I will show a microphysical model where mDM is shocked by a supernova remnant and isotropized in the frame of the expanding fluid. We find that for $|q_\chi/m_\chi| > 10^{-13} e/{\rm MeV}$, the isotropization length for electromagnetic...
We review a dark matter scenario [1-6] which is consistent with recent analyses of observations from Fermi-LAT, AMS-02, and Planck. In this scenario, with both supersymmetry and an extended Higgs sector, the mass of the dominant dark matter WIMP is rigorously ≤ 125 GeV/c$^2$, its gauge couplings are precisely defined, and its Higgs-mediated couplings should be comparable to those of a...
GRAMS (Gamma-Ray and AntiMatter Survey) is a next-generation
experiment that will be the first to target both MeV gamma-ray
observations and antimatter-based indirect dark matter searches. With
a cost-effective, large-scale LArTPC detector, a single long-duration
balloon (LDB) flight can have an order of magnitude improved
sensitivity to gamma rays in the poorly-explored MeV energy...
Title: Dark Stars
Abstract: The first phase of stellar evolution in the history of the
Universe may be Dark Stars (DS), powered by dark matter heating rather than
by nuclear fusion. Weakly Interacting Massive Particles which can be their own antipartners can collect inside the first stars and annihilate to produce
a heat source that powers the stars. Alternatively, Self Interacting...
PandaX dark matter experiments use liquid xenon as target to search for dark matter particles at the China Jinping Underground Laboratory. The second phase of the experiments, PandaX-II, with 580 kg liquid xenon in the sensitive volume, has finished data taking in 2019 and collected 140 ton day of dark matter search data set in total. The next experiment under preparation, PandaX-4T, with 4...
The results of the first 6 independent annual cycles of DAMA/LIBRA–phase2 experiment deep underground at Gran Sasso are summarized; they correspond to a total exposure of 1.13 ton × yr. The DAMA/LIBRA–phase2, with lower energy threshold with respect to phase1, confirms the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature, at...
The SuperCDMS SNOLAB experiment will probe a range of low-mass dark matter models with a suite of silicon and germanium detectors operated in both high-voltage and nuclear-recoil-discrimination modes. Plans for nuclear recoil yield measurements and our 4-tower initial payload strategy will be presented, as well as our expected physics reach for the first science run and beyond.
DEAP-3600 is a dark matter direct detection experiment located 2 km underground at SNOLAB (Sudbury, Canada). This single-phase detector consists of 3.3 tonnes of liquid argon (LAr), with an array of 255 photomultiplier tubes viewed through 50 cm of acrylic. The collaboration released dark matter search results from the first year of running (November 2016 to October 2017) last year, with a...
DAMIC-M is a next-generation experiment to search for dark matter with charge coupled devices (CCDs) in the Modane Underground Laboratory in France. It builds on the success of DAMIC at SNOLAB, which pioneered the detection of nuclear and electronic recoils in the bulk silicon of CCDs deployed in a low-background environment. The dominant source of noise in conventional CCDs lie in their...
COSINE-100 is a direct detection dark matter experiment that is testing DAMA/LIBRA’s claim of dark matter discovery. Located in South Korea’s Yangyang Underground Lab, COSINE-100 comprises 106 kg of sodium iodide detectors surrounded by a ~2000 L liquid scintillator veto. In this talk, I will discuss recent results from our experiment, including searches for a dark matter-induced annual...
ANAIS (annual modulation with NaI Scintillators) is a dark matter direct detection experiment
located at the Canfranc Underground Laboratory (LSC, Spain).
Its main goal is to test in a model independent way the DAMA/LIBRA
positive result: an annual modulation in the low-energy detection rate compatible
with the expected signal induced by WIMPs in the galactic halo.
ANAIS-112,...
PICO-40L is the most advanced bubble chamber using about 50kg of a fluorine rich target material. The detector has a new chamber concept without buffer fluid, eliminating the backgrounds associated with the water in contact with the active liquid in previous PICO bubble chambers. We will report the status of the commissioning and give a first indication of the background rates in the chamber.
We report the final dark matter (DM) search results and background spectrum measurement from a 1.2 g·day exposure of an upgraded SuperCDMS high-voltage eV-resolution (HVeV) detector. The 1×1×0.4 cm3 (0.93 g) HVeV detector is able to detect single electron-hole pair production by sensing phonons produced by the Neganov-Trofimov-Luke effect at a voltage bias of 100 V. Relative to the...
The DarkSide multi-stage program aims to search for WIMPs by building and operating a dual phase liquid Argon (LAr) time projection chamber (TPC). The upcoming DarkSide-20k detector, with a fiducial mass of 20 tonnes of depleted liquid Argon, will operate in the underground laboratories of “Laboratori Nazionali del Gran Sasso”. The photodetection relies on Silicon photomultipliers (SiPMs)....
Superfluid He-4 is a promising target material for direct detection of light (< 1 GeV) dark matter. Signal channels for dark matter - nucleus interactions in superfluid helium include prompt photons, triplet excimers, rotons and phonons, but measurement of these signal strengths have yet to be performed for low energy nuclear recoils. A measurement of the prompt scintillation yield from...
LUX-ZEPLIN (LZ) is a direct detection dark matter experiment, currently under construction 4850ft underground at the Sanford Underground Research Facility in Lead, SD, USA. At the core of the LZ design is a dual-phase liquid Xe time projection chamber (TPC) with a 7 ton active mass. This experiment will achieve a sensitivity of 1.6$\times$10$^{-48}$ cm$^2$ to 40 GeV/c$^2$ WIMPs in a 1000 day...
The two-phase liquid xenon time projection chamber is one of the leading technologies used for dark matter direct detection. World-leading limits on dark matter interactions have been set by LUX and XENON1T, and the upcoming LZ and XENONnT experiments seek to push further. A crucial part of using this technology is being able to classify energy deposits as nuclear recoils (NR) or electron...
The PICO collaboration searches for dark matter particles using superheated fluid detectors, or bubble chambers, filled with fluorine-rich targets. These detectors can be made inherently insensitive to electron recoils, while additional background suppression is achieved with the acoustic signature of the bubble nucleation that allows the identification of alpha particles. In this talk I will...
The CYGNUS collaboration is developing a range of approaches towards a global dark matter experiment in the form of an array of nuclear recoil direction sensitive detectors, distributed at multiple underground sites. Here we describe demonstration of two new hybrid TPC charge readout concepts for CYGNUS, capable of use with SF6 negative ion gas. The first comprises a thick GEM gain stage...
The LUX collaboration has pioneered new techniques in the quest of solving the dark matter puzzle. Using liquid xenon (LXe) dual-phase TPC technologies,
the collaboration set several world leading limits on WIMP dark matter. Even after the detector decommissioning in 2016 the analysis work continues. In this presentation, I will give an overview of the recent results published by the LUX...
Liquid argon targets in WIMP search detectors provide outstanding separation between nuclear and electron recoil signals via pulse-shape discrimination of the scintillation signals. Atmospheric argon (AAr), however, has a naturally occurring radioactive isotope, $^{39}$Ar, a $\beta$ emitter of cosmogenic origin. For large detectors, the atmospheric $^{39}$Ar activity poses pile-up concerns....
DarkSide-20k, is designed as a 20-tonne fiducial mass Time Projection Chamber with SiPM based photosensors, expected to be free of any instrumental background for an exposure of >100 ton x years.
The dual phase TPC will use a total of 50 t low radioactivity Argon from underground source and will be realized within a sealed acrylic vessel surrounded by an active neutron veto detector. The...
The nature and origin of Dark Matter are among the most compelling mysteries of contemporary science. For over three decades, physicists have been trying to detect Dark Matter particles via collisions on target nuclei, with little success.
The LZ collaboration is building a massive Dark Matter detector, which is currently being installed at the 4850 level of the Sanford Underground Research...
To date, dark matter has only been observed through its gravitational interaction. A new detector in the XENON family, XENONnT, is being constructed at the INFN Gran Sasso National Laboratory in Italy, featuring a $6$ tonnes of liquid xenon target contained in a larger time projection chamber. The large target mass and approximately 10 times lower background than its predecessor XENON1T, will...
Two of the outstanding open questions in physics are the nature of dark matter and the fundamental nature of neutrinos. DARWIN is a next-generation experiment aiming to reach a dark matter sensitivity limited by the irreducible neutrino backgrounds. The core of the detector will have a 40 ton liquid xenon target operated as a dual-phase time projection chamber. The unprecedented large xenon...
The Scintillating Bubble Chamber (SBC) is a rapidly developing new technology for sub-keV nuclear recoil detection. Demonstrations in liquid xenon at the few-gram scale have confirmed that this technique combines the event-by-event energy resolution of a liquid-noble scintillation detector with the world-leading electron-recoil discrimination capability of the bubble chamber, and in fact...
Large mass liquid xenon detectors, such as LUX-ZEPLIN (LZ) and XENONnT, are leading the search for dark matter particles with masses above ~5 GeV/c^2, with both spin-dependent and spin-independent couplings. HydroX is a new effort to dissolve hydrogen into liquid xenon to allow these experiments to probe sub-GeV/c^2 dark matter. The use of hydrogen-doped xenon takes advantage of the kinematic...
A large experimental program is underway to extend the sensitivity of direct detection experiments, searching for interaction of Dark Matter with nuclei, down to the neutrino floor. However, such experiments are becoming increasingly difficult and costly due to the large target masses and exquisite background rejection needed for the necessary improvements in sensitivity. We investigate an...
Sub-GeV dark matter (DM) which interacts with electrons can excite electrons occupying molecular orbitals in a scattering event. In particular, aromatic compounds such as benzene or xylene
have an electronic excitation energy of a few eV, making them sensitive to DM as light as a few
MeV. These compounds are often used as solvents in organic scintillators, where the de-excitation
process...
The DarkSide collaboration demonstrated the ability of a dual-phase LAr-TPC to
search for low-mass dark matter candidates, including light WIMPs with masses
below 10- GeV and sub-GeV particles that interact with couplings smaller than
the weak scale, by exploiting the high electron extraction efficiency and the
inherent gain of the ionization signal of the DarkSide-50 detector. A...
CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) is a direct dark matter search experiment located at the Gran Sasso underground Laboratory (LNGS, Italy). Scintillating CaWO4 crystals, operated as cryogenic calorimeters at millikelvin temperature, are used as target material for elastic DM-nucleus scattering. The experiment, optimized for low-energy nuclear recoil...
I will present results from ongoing characterization of the skipper CCD technology, and progress towards deployment of the 100-gram experiment using a new generation of skipper CCDs at the SNOLAB deep underground facility.
The Super Cryogenic Dark Matter Search (SuperCDMS) employs cryogenic germanium and silicon detectors to search for dark matter with a focus on low-mass dark matter particles. As SuperCDMS prepares for the next generation facility to come online at SNOLAB, new detectors are tested at the Cryogenic Underground TEst facility (CUTE), which provides a low-background environment and thus presents...
The NEWS-G (New Experiments With Spheres – Gas) collaboration searches for light dark matter using spherical proportional counters (SPCs) located in deep underground laboratories. A choice of light gas targets (Ne, He, H) in conjunction with sub-KeV nuclear recoil thresholds allow for sensitivity to low-mass WIMPs (Weakly Interacting Massive Particles) down to 0.1 GeV/c^2. The recent results...
A large directional nuclear recoil observatory could be used to observe and distinguish different neutrino sources, to search for dark matter in the presence of irreducible background, including neutrinos, and to demonstrate the cosmological origin of a dark matter signal. With WIMP-nucleon scattering limits approaching the neutrino floor, and coherent neutrino-nucleon scattering...
The QCD axion is a compelling dark-matter candidate. The axion is a hypothetical particle, arising from the Pecci-Quinn solution to the strong CP problem in quantum chromodynamics. The Axion Dark Matter eXperiment (ADMX) is searching for cold dark matter axions in the halo of our galaxy. ADMX is the largest operating axion haloscope. It consists of a high-$Q$ microwave resonator immersed in a...
The QCD axion is an excellent light dark matter candidate, while also
naturally explaining CP-conservation in strong interactions. Axions
generated after inflation are expected to have masses around 100µeV,
which is at present inaccessible by existing cavity searches.
Galactic axions can be converted to electromagnetic radiation at
boundaries between different dielectric constants under a...
The Haloscope At Yale Sensitive To Axion Cold dark matter (HAYSTAC) is a pathfinder and an innovation testbed for the 2.5-12 GHz (10-50 μeV) mass range. Operational since 2015, it has from the beginning utilized Josephson Parametric Amplifiers which have enabled it to achieve a system noise temperature at only 2x the Standard Quantum Limit (SQL), and thus probe in the QCD model band at masses...
Particle physics models with Peccei-Quinn (PQ) symmetry breaking
as a consequence of supersymmetry (SUSY) breaking are attractive in that
they solve the strong CP problem with a SUSY DFSZ-like axion,
link the SUSY breaking and PQ breaking intermediate mass scales
and can resolve the SUSY $\mu$ problem with a naturalness-required
weak scale $\mu$ term whilst soft SUSY breaking terms...
