Conveners
Dark Matter and Astroparticle Physics
- Stefania Gori (UC Santa Cruz)
Dark Matter and Astroparticle Physics
- Stefania Gori (UC Santa Cruz)
Dark Matter and Astroparticle Physics
- Wenyu Wang (Beijing University of Technology)
Dark Matter and Astroparticle Physics
- Wenyu Wang (Beijing University of Technology)
Dark Matter and Astroparticle Physics
- Yang Bai (University of Wisconsin, Madison)
Dark Matter and Astroparticle Physics
- Pyungwon Ko (Korea Inst. for Advanced Study (KIAS))
Dark Matter and Astroparticle Physics
- Pyungwon Ko (Korea Inst. for Advanced Study (KIAS))
Dark Matter and Astroparticle Physics
- Yang Bai (University of Wisconsin, Madison)
Dark Matter and Astroparticle Physics
- Wenyu Wang (Beijing University of Technology)
Dark Matter and Astroparticle Physics
- Yang Bai (University of Wisconsin, Madison)
Dark Matter and Astroparticle Physics
- Haipeng An (Tsinghua University)
Dark Matter and Astroparticle Physics
- Haipeng An (Tsinghua University)
Dark Matter and Astroparticle Physics
- Yang Bai (University of Wisconsin, Madison)
The SBC Collaboration is constructing a 10-kg liquid argon bubble chamber with scintillation readouts. The goal is to achieve 100 eV nuclear recoils detection with near-complete discrimination against electron recoil events. In addition to a dark matter search, SBC targets a CEvNS measurement of MeV-scale neutrinos from nuclear reactors. A high-statistics, high signal-to-background detection...
The dark sector may be as rich and varied as the standard model. Twin Higgs models, which explain the little hierarchy problem, provide a compelling and predictive realization of such a dark sector, where the standard model field content is copied in a hidden sector. I show how spontaneously breaking the twin color can naturally lead to asymmetric dark matter and baryogenesis in addition to...
Primordial black holes (PBH) are a natural and generic dark matter candidate in supersymmetry. In the early universe, the flat directions of supersymmetry form scalar condensates with large expectation values. These condensates can subsequently fragment into non-topological solitons, SUSY Q-balls, which become the building blocks of PBHs. The PBH masses resulting from supersymmetry naturally...
The observation of 236 MeV muon neutrinos from kaon-decay-at-rest (KDAR) originating in the core of the Sun would provide a unique signature of dark matter annihilation. Since excellent angle and energy reconstruction are necessary to detect this monoenergetic, directional neutrino flux, DUNE with its vast volume and reconstruction capabilities, is a promising candidate for a KDAR neutrino...
If the dark matter annihilation cross-section is velocity-dependent, then gamma-ray signals from astrophysical targets depend non-trivially on the dark matter velocity distribution. Since different targets can have different characteristic velocity scales, analyses of ensembles of targets can potentially find evidence for particular scenarios of dark matter microphysics. We discuss recent...
Extensive searches to probe the particle nature of dark matter (DM) have been going on for some decades now but, so far, no conclusive evidence has been found. Among various options, the Weakly Interacting Massive Particles (WIMP) remains one of the prime
possibilities as candidates for DM near the TeV scale. Taking a phenomenological view, such null results may be explained for a generic...
We revisit the Higgs-invisible decay branching ratio in Higgs-portal dark matter models.
If the mass of the dark matter is slightly below the half of the mass of the Higgs boson, then pairs of the DM particles annihilate into the SM particles efficiently thanks to the Higgs resonance. The DM-Higgs coupling is required to be small to obtain the right amount of the dark matter relic abundance....
We study observable signals from dark matter that self-annihilates via Sommerfeld effect in dwarf spheroidal galaxies (dSphs). Since the effect of the Sommerfeld enhancement depends on the velocity of dark matter, it is crucial to determine the profile of dSphs to compute the J-factor, i.e., the line-of-sight integral of density squared. In our study we use the prior distributions of the...
We revisit the scalar singlet dark matter (DM) accompanied by vectorlike dark leptons in two scenarios: in case I, the dark sector consists of a Dirac fermionic doublet; while in case II, a doublet fermion and a singlet. In both cases, the dark leptons couple with other dark sector particles and the Standard Model (SM) via gauge and Yukawa interactions. As a result, (i) new DM annihilation...
In this talk, I will present the phenomenology of dark-matter production in the case where it is both produced by a freeze-out or freeze-in mechanism and by the evaporation of primordial black holes. I will show that the presence of a vector mediator between the hidden and the visible sector affects the production of dark-matter particles as well as its phase space distribution. I will also...
A fraction of the dark matter in the solar neighborhood might be composed of non-galactic particles with speeds larger than the escape velocity of the Milky Way. The non-galactic dark matter flux would enhance the sensitivity of direct detection experiments, due to the larger momentum transfer to the target. In this note, we calculate the impact of the dark matter flux from the Local Group and...
The Belle II experiment at the asymmetric $e^+e^-$ collider, SuperKEKB, is a substantial upgrade of the Belle/KEKB experiment. Belle II aims to record 50 ab$^{-1}$ of data over the course of the project. During the first physics runs in 2018-2020, around 100 fb$^{-1}$ of data were collected. These early data include specifically-designed low-multiplicity triggers which allow a variety of...
The non-observation of conclusive WIMP signals raises the question whether WIMPs can still account for the dark matter of the universe. In this talk I will present results from a global analysis of effective field theory operators describing the interactions between WIMPs and Standard Model particles. In this bottom-up approach, the global fitting framework GAMBIT is used to simultaneously...
Feebly Interacting Massive Particles (FIMPs) are dark matter candidates that never thermalize in the early universe and whose production takes place via decays and/or scatterings of thermal bath particles. If FIMPs interactions with the thermal bath are renormalizable, a scenario which is known as freeze-in, production is most efficient at temperatures around the mass of the bath particles and...
Extensions of the two higgs doublet models with a singlet scalar can easily accommodate all current experi-
mental constraints and are highly motivated candidates for Beyond Standard Model Physics. It can success-
fully provide a dark matter candidate, explain baryogenesis and provide gravitational wave signals. In this
work, we focus on the dark matter phenomenology of the two higgs...
I describe a reanalysis of data sets that have previously been found to harbor evidence for an unidentified X-ray line at 3.5 keV in order to quantify the robustness of earlier results that found significant evidence for a new X-ray line at this energy. The 3.5 keV line is intriguing in part because of possible connections to dark matter. We analyze observations from the XMM-Newton and...
The search for dark matter (DM) weakly interacting massive particles with noble elements has probed masses down and below a GeV/c^2. The ultimate limit is represented by the experimental threshold on the energy transfer to the nuclear recoil. Currently, the experimental sensitivity has reached a threshold equivalent to a few ionization electrons. In these conditions, the contribution of a...
Abstract: A large amount of data from dwarf galaxies to galaxy clusters appears to indicate that dark matter (DM) acts like a collisional fluid at galaxy scales to a collisionless fluid at the scale of galaxy clusters. We will discuss a particle physics model with the standard model extended with a gauged abelian hidden sector to explain this phenomenon. In this model dark matter consists of...
We introduce WimPyDD, a modular, object–oriented and customizable Python code that calculates accurate predictions for the expected rates in WIMP direct–detection experiments within the framework of Galilean–invariant non–relativistic effective theory in virtually any scenario, including inelastic scattering, an arbitrary WIMP spin and a generic WIMP velocity distribution in the Galactic halo....
The first results of the Fermilab Muon $g−2$ experiment are in full agreement with the previous BNL measurement and push the world average deviation in $\Delta a_\mu$ from the Standard Model to 4.2 $\sigma$. In this talk I will present an extensive survey of its impact on beyond the Standard Model physics, focusing on simple extensions of the standard model, based on arXiv:2104.03691. In...
A pseudo-Nambu-Goldstone boson (pNGB) is an attractive candidate for dark matter due to the simple evasion of the current severe limits of dark matter direct detection experiments. One of the pNGB dark matter models has been proposed based on a gauged U(1) B−L symmetry. The pNGB has long enough lifetime to be a dark matter and thermal relic abundance can be fit with the observed value against...
We discuss a model with dark sector described by non-Abelian $SU(2)_D$ gauge symmetry where we introduce $SU(2)_L \times SU(2)_D$ bi-doublet vector-like leptons to generate active neutrino masses and kinetic mixing between $SU(2)_D$ and $U(1)_Y$ gauge fields at one-loop level. After spontaneous symmetry breaking of $SU(2)_D$, we have remnant $Z_4$ symmetry guaranteeing stability of dark matter...
Radiation produced by decaying/annihilating dark matter (DM) and evaporating primordial black holes (PBH) can ionize and heat up intergalactic medium (IGM) before reionization. Such effects can be efficiently probed using observations of cosmic microwave background (CMB) and 21cm signal of neutral hydrogen. In this talk I will show that CMB data from Planck and 21cm data from EDGES can set...
We present a dark matter model to explain the excess events in the electron recoil data recently reported by the Xenon1T experiment. In our model, dark matter annihilates into a pair of on-shell particles , which subsequently decay into the final state; interacts with electrons to generate the observed excess events. Because of the mass hierarchy, the velocity of can be rather large and can...
We study the prospects for indirect detection of dark matter (DM) in the Sun and in the Galactic halo using the Hyper-Kamiokande (HyperK) neutrino experiment, currently under construction. We undertook a dedicated simulation of the HyperK detector, which we benchmarked against results from the Super-Kamiokande (SuperK) experiment and HyperK physics projections. For DM annihilation to neutrino...
White dwarfs are the most abundant stellar remnants. They provide a promising means of probing dark matter (DM) interactions complimentary to direct searches. The scattering of DM off stellar constituents, ions or degenerate electrons, leads to gravitational capture, with important observational consequences. In particular, white dwarf heating due to the energy transfer in the DM capture and...
Cosmic photons from astrophysical sources are ideal for investigating the Lorentz symmetry violation (LV). A series of studies on high energy gamma-ray burst (GRB) photons suggest a light speed variation with linear energy dependence at the Lorentz violation scale of $3.6*10^{17}$ GeV, with subluminal propagation of high energy photons in cosmological space. Constraints on Lorentz violation...
We demonstrate the impact of non-perturbative effects on the annihilation cross section of DM in a model of simplified t-channel DM. Specifically, we study the case of Majorana fermion DM coupling to the standard model (SM) quarks via a colored scalar.
For DM masses in the GeV-TeV range, direct detection experiments strongly constrain the DM coupling to the SM quarks. From a cosmological...
We examine the implications of non-standard cosmologies (NSCs) on Dark Matter. We present a detailed analysis of the impact of NSCs on frozen-in relics and examine their lower allowed mass limit. Moreover, we discuss how the ``natural" axion window can be extended, which can potentially help us to exclude NSCs once the axion is discovered.
High energy $e^+e^-$ colliders offer unique possibility for the most general search for dark matter (DM) based on the mono-photon signature. As any $e^+e^-$ collision processmay include hard initial-state photon radiation, analysis of the energy spectrum and angular distributions of observed photons can be used to search for hard processes with an invisible final state.
We consider...
We study the connection between neutrino mass and two unsolved cosmological problems: the existence of dark matter (DM) and matter-antimatter asymmetry. To have a testable connection, we consider the low energy type Ib seesaw mechanism instead of the traditional type I seesaw mechanism. In the minimal type Ib seesaw mechanism, the effective neutrino mass operator involves two different Higgs...
Innovative experimental techniques are needed to further search for dark matter weakly interacting massive particles. The ultimate limit is represented by the ability to efficiently reconstruct and identify nuclear and electron recoil events at the experimental energy threshold. Gaseous Time Projection Chambers (TPC) with optical readout are very promising candidates thanks to the 3D event...
Searches in CMS for dark matter particles, mediators, and dark sector extensions will be presented. Various final states, topologies, and kinematic variables are explored utilizing the full Run-II data-set collected at the LHC.
We point out a novel role for the Standard Model neutrino in dark matter phenomenology where the exchange of neutrinos generates a long-range potential between dark matter particles. The resulting dark matter self interaction could be sufficiently strong to impact small-scale structure formation, without the need of any dark force carrier. This is a generic feature of theories where dark...
DEAP-3600 is a dark matter direct detection experiment running at the SNOLAB in Sudbury, Canada. The spherical detector is situated 2 km below the earth's surface with a low cosmic muon background environment consisting of 3.3 tonnes of liquid argon target surrounded by an array of 255 photomultiplier tubes. The major backgrounds for DEAP-3600 come from alpha particles induced by dust...
I will discuss the Higgs-portal dark matter scenario in the 5-dimensional brane world cosmology, such as Randall-Sundrum cosmology and Gauss-Bonnet cosmology.
We study for the first time the possibility of probing long-range fifth forces utilizing asteroid astrometric data, via the fifth force-induced orbital precession. We examine nine Near-Earth Object (NEO) asteroids whose orbital trajectories are accurately determined via optical and radar astrometry. Focusing on a Yukawa-type potential mediated by a new gauge field (dark photon) or a...
In recent years, the usefulness of astrophysical objects as Dark Matter (DM) probes has become more and more evident, especially in view of null results from direct detection and particle production experiments. The potentially observable signatures of DM gravitationally trapped inside a star, or another compact astrophysical object, have been used to forecast stringent constraints on the...
Multiple microlensing surveys have been conducted to place limits on primordial black holes in nearby dark matter halos. We show that these existing limits on PBHs can be recast to constrain dark matter lenses that are more spatially extended than PBHs. As two representative cases, we examine NFW subhalos and boson stars, which are predicted in many models such as axion miniclusters and axion...
Right-handed neutrinos appear in several extensions beyond the Standard Model, specially in connection to neutrino masses. Weak scale right-handed neutrino dark matter constructions are typically rather constrained by data. In this work, we carry out the dark matter phenomenology of a weak scale right-handed neutrino dark matter, within a type I seesaw model, in the presence of a fast early...
Axions, if they exist, can be produced efficiently in white dwarfs, free-stream out of the star due to their weak interactions with matter, and then be converted to a photon in the stellar magnetosphere. X-ray telescope observations of these stars can provide strong constraints on the coupling to electromagnetism and matter. I discuss the results of the first dedicated observation of a...
We present several models of asymmetric dark matter (ADM) and baryons coming from dark phase transitions and unique complementary signals. One achieves both baryogenesis and ADM in a minimal "mirror" sector, while another adds (heavy) ADM to any standard baryogenesis scenario. Yet another uses the most minimal dark sector to achieve baryogenesis alone. Thanks to the necessity of the vector and...
The far detector of the Deep Underground Neutrino Experiment (DUNE) comprising four liquid argon time projection chambers (LArTPCs) totaling 70-kton mass will be installed at a depth of 1,500 m at the Sanford Underground Research Facility. Thanks to its large volume and the LArTPC-based precision imaging capability, the DUNE far detector can probe signals of cosmic origin. Of these, boosted...
Design goals for future neutrino experiments, including high-intensity proton beams and precise detectors, provide an opportunity to explore physics beyond the standard model. Dark matter accounts for 27% of our universe, but it’s particle nature remains to be uncovered, and many efforts have been made to elucidate the properties of dark matter.
The DUNE experiment uses high-intensity 120 GeV...
I will introduce an SU(3)C × SU(2)L × U(1)Y × U(1)B-L model, in which the neutrino masses and mixing can be generated via Type-I seesaw mechanism after U(1)B-L breaking. A light mediator emerges and enables non-standard interaction that violates the lepton number. It shows that the non-standard interaction leads to low energy recoil events that is consistent with the observed KeV range...
Beyond their unprecedented sensitivity to dark matter (DM), as I will demonstrate, large direct detection experiments constitute impressive neutrino telescopes. This opens a new window into astronomy, leading to possible insights into major problems such as the origin of supermassive black holes. Furthermore, DM experiments can be exploited as novel tools in multi-messenger astronomy for...
Dark photon as an ultralight dark matter candidate can interact with the Standard Model particles via kinetic mixing. We propose to search for the ultralight dark photon dark matter using radio telescopes with solar observations. The dark photon dark matter can efficiently convert into photons in the outermost region of the solar atmosphere, the solar corona, where the plasma mass of photons...
Primordial black holes (PBHs), possibly formed via gravitational collapse of large density perturbations in the very early universe, are one of the earliest proposed and viable dark matter (DM) candidates. Recent studies indicate that PBHs can make up a large or even entire fraction of the present day DM density for a wide range of masses. Ultralight
PBHs in the mass range of 10^{15} -...
We propose an appealing alternative scenario of leptogenesis assisted by dark
sector which leads to the baryon asymmetry of the Universe satisfying all theoretical and
experimental constraints. The dark sector carries a non minimal set up of singlet doublet
fermionic dark matter extended with copies of a real singlet scalar field. A small Majorana
mass term for the singlet dark fermion, in...
Dark, chiral fermions carrying lepton flavor quantum numbers are natural candidates for freeze-in. Small couplings with the Standard Model fermions of the order of lepton Yukawas are ‘automatic’ in the limit of Minimal Flavor Violation. In the absence of total lepton number violating interactions, particles with certain representations under the flavor group remain absolutely stable. For...
The Belle experiment at the KEKB asymmetric-energy e^+e^- collider has accumulated close to $1\,{\rm ab}^{-1}$ of data in electron-positron collisions at center-of-mass energies around various $\Upsilon(nS)$ resonances. These data can be used to perform a number of new physics searches in the context of dark sector with an unprecedented precision.
We present the results of a search of the...
Inspired by the fact that relatively small values of the effective higgsino mass parameter of the Z3-symmetric Next-to-Minimal Supersymmetric Standard Model (NMSSM) could render the scenario ‘natural’, we explore the plausibility of having relatively light neutralinos and charginos (the electroweakinos or the ewinos) in such a scenario with a rather light singlino-like Lightest Supersymmetric...
We study the impact of thermalization and number-changing processes in the dark sector on the yield of gravitationally produced dark matter (DM). We take into account the DM production through the $s$-channel exchange of a massless graviton both from the scattering of inflatons during the reheating era, and from the Standard Model bath via the UV freeze-in mechanism. By considering the DM to...
The discovery of diffuse sub-PeV gamma-rays by the Tibet AS$_\gamma$ collaboration promises to revolutionize our understanding of the high-energy astrophysical universe. It has been shown that this data broadly agrees with prior theoretical expectations. We study the impact of this discovery on a well-motivated new physics scenario: PeV-scale decaying dark matter (DM). Considering a wide...
We make a comprehensive study of vector-like fermionic dark matter and flavor anomalies in a simple extension of standard model. The model is added with doublet vector-like fermions of quark and lepton type, and also a $S_1(\bar{\textbf{3}},\textbf{1},1/3)$ scalar leptoquark. An additional lepton type singlet fermion is included, whose admixture with vector-like lepton doublet plays the role...
New physics may have gone unseen so far due to it being hidden in a dark sector. This may result in a rich phenomenology which we can access through portal interactions. In this talk, we present recent results from dark-sector searches in CMS using the full Run-II data-set of the LHC.
We discuss the possibility that accreting black hole systems could be sources for dark matter flux through several different mechanisms. We firstly discuss two types of systems: coronal thermal plasmas around supermassive black holes in active galactic nuclei (AGNs), and accretion disks of stellar-mass X-ray black hole binaries (BHBs). We explore how these black hole systems may produce keV...
A recently proposed dark matter WIMP [1] has only second-order couplings to gauge bosons and itself. As a result, it has small annihilation, scattering, and creation cross-sections, and is consequently consistent with all current experiments and the observed abundance of dark matter. These cross-sections are, however, still sufficiently large to enable detection in experiments that are planned...
The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS experiment has developed a broad search program for DM candidates, including resonance searches for the mediator which would couple DM to the SM,...
