Gravitational lensing is a powerful tool for constraining the nature and distribution of dark matter. Strong lensing observations allow comparisons between the mass and light profiles of galaxies, and dark matter subhalos have been detected through their perturbations to lensed images. Weak lensing probes the matter power spectrum, and thus the abundance and behaviour of dark matter, as well...
Background stars at cosmological distances that appear near the critical curves of galaxy clusters can be magnified by extreme factors of O(1000) and be detectable in deep observations with the Hubble or James Webb space telescopes. The stellar nature of this objects can be confirmed thanks to microlensing by stars in the galaxy cluster that can temporarily boost the flux of the lensed star by...
The so-called "strongly interacting massive particles" (SIMPs) refer to a class of dark matter candidates with the relic abundance set by the 3$\to$2 interactions which allows for dark matter with sub-GeV masses, not yet strongly constrained by direct detection experiments. Interestingly, SIMP dark matter features relatively strong self-interactions that may explain the small-scale structure...
We show how cogenesis of dark matter and baryon asymnmetry can arise from kinetic misalignment of the QCD axion. For this, we work out the DFSZ and KSVZ axion models associated with the type-I seesaw mechanism and the PQ inflacion.
The origin of neutrino masses remains unknown to date. One popular idea involves interactions between neutrinos and ultralight dark matter, described as fields or particles with masses $m_\phi \lesssim 10\,\mathrm{eV}$. Due to the large phase-space number density, this type of dark matter exists in coherent states and can be effectively described by an oscillating classical field. As a result,...
The null results of dark matter searches targeting weakly interacting massive particles (WIMPs) put increasing pressure on the simplest realizations of WIMP models. In response, we explore an extended dark sector with a non-trivial flavor structure within the Dark Minimal Flavor Violation (DMFV) framework. These models extend the standard dark matter paradigm by introducing flavor-dependent...
Despite the robust cosmological and astrophysical evidence confirming the existence of a non-baryonic matter component in the Universe, the underlying nature of Dark Matter (DM) remains a mystery. Among the several possible scenarios, light DM candidates thermally produced in the early Universe are especially interesting, since their abundance could be set via the standard freeze-out...
Sub-GeV dark matter (DM) has been gaining significant interest in recent years, since it can account for the thermal relic abundance while evading nuclear recoil direct detection constraints. However, sub-GeV DM is still subject to a number of constraints from laboratory experiments, and from astrophysical and cosmological observations. In this work, we compare these observations with the...
Many dark matter models become unviable when embedded into the framework of asymptotically safe quantum gravity. In this work, we investigate dark matter arising as bound states of fundamental fermions in the strongly-coupled regime of a gauge theory. Modeling the self-interactions of dark baryons via the effective-range approach, we perform a multi-scale analysis in which we combine...
Ultra-heavy dark matter is a class of candidates for which direct detection experiments are ineffective due to the suppressed dark matter flux. We explore the potential of large underwater acoustic arrays, developed for ultra-high energy neutrino detection, to detect ultra-heavy dark matter. As ultra-heavy dark matter traverses seawater, it deposits energy through nuclear scattering,...
Halo dark matter particles with sub-GeV masses do not have sufficient kinetic energy to induce detectable recoils of heavy nuclei in the detectors, direct detection experiments, hence, loose sensitivity to such light dark matter. Dark matter particles can be, however, accelerated by different mechanisms and even light dark matter can then provide observable signatures. These signatures include...
Direct detection experiments aim to shed light on the thus far elusive nature of dark matter through measuring its potential interactions with ordinary matter. This talk will provide an overview of these experiments and the status of the field. After briefly summarising the possible dark matter candidates, I will cover some of the detection strategies and recent results, before discussing the...
Direct detection experiments look for scattering events of dark matter with known Standard Model particles. Scattering on heavy nuclei is a promising approach to searching for heavy (above a few GeV) dark matter candidates. Liquid noble elements, like xenon, are especially suited because of their inert behavior, ability to be purified and be low in radioactivity.
XENONnT is the result of two...
The DAMIC-M (DArk Matter In CCDs at Modane) experiment will use Skipper CCDs to search for low-mass (sub-GeV) dark matter underground at the Laboratoire Souterrain de Modane (LSM). With approximately 0.7 kg of silicon target mass and sub-electron energy resolution, the detector will exceed both the exposure and energy threshold (eV scale) of previous experiments. These capabilities will grant...
The NEWS-G collaboration is searching for light dark matter using spherical proportional counters [1]. Access to 50 MeV to 10 GeV mass range is enabled by the combination of single electron threshold, light gaseous targets (H, He, Ne), and highly radio-pure detector construction. Most recently, new constraints on spin-dependent
interactions of dark matter with protons were obtained [2] with...
BULLKID-DM is a new experiment aimed at searching for hypothetical
WIMP-like Dark-Matter particles with mass around 1 GeV or below and
cross-section with nucleons smaller than $10^{-41}$ cm$^{2}$. The
target detector consists of a stack of diced silicon phonon collectors,
acting as an array of particle absorbers sensed by multiplexed Kinetic
Inductance Detectors (KIDs). The target will...
We present a dynamically self-consistent model of the Milky Way constrained by Gaia observations, which includes a radially anisotropic dark matter (DM) halo component. The component is the result of a galaxy merger and affects the DM velocity distribution functions, which in turn affects the measured DM flux in both heliocentric and geocentric reference frames. Comparing our model with...
The RADES (Relic Axion Detection Exploratory Setup) team originated in 2016 for the search of dark matter axions with haloscopes. Recently, the RADES collaboration has produced their most sensitive physics results for axion masses around 36.56 µeV. This team has made further research advances in topics such as the design of cylindrical (for operation at the MPP Bluefors system) and...
Galaxy simulations provide a powerful framework for testing dark matter models by linking theoretical predictions to observable structures across cosmic scales. By studying the formation and evolution of galaxies in different dark matter scenarios, simulations help identify signatures that could distinguish between cold dark matter and alternative models. Low surface brightness features, such...
The small-scale distribution of dark matter (DM) remains a key challenge in modern cosmology. While the ΛCDM paradigm successfully describes large-scale structure formation, tensions persist at galactic and sub-galactic scales, particularly in the abundance and internal structure of dwarf galaxies. Warm dark matter (WDM) has emerged as a compelling alternative to cold dark matter (CDM), as its...
A number of studies assert that dark matter (DM) subhaloes without a baryonic counterpart and with an inner cusp always survive no matter the strength of the tidal force they undergo.
In this work, we perform a suite of numerical simulations specifically designed to analyse the evolution of the circular velocity peaks ($V_\mathrm{max}$, and its radial value $r_\mathrm{max}$) of low-mass DM...
Fuzzy dark matter (FDM) is a compelling candidate for dark matter, offering a natural explanation for the structure of diffuse low-mass haloes. However, the canonical FDM model with a mass of $10^{-22}~{\rm eV}$ encounters challenges in reproducing the observed diversity of dwarf galaxies, except for possibly scenarios where strong galactic feedback is invoked. The introduction of...
Deep learning has quickly become a valuable tool in the quest to understand dark matter, helping researchers explore faint signals across a range of experiments—from high-energy colliders to direct and indirect searches. By sifting through vast datasets and uncovering subtle patterns, these techniques can reveal signs of dark matter that traditional approaches might miss. This talk provides a ...
Detecting dark (matter) subhalos on sub-galactic scales could offer critical insights into the nature of DM, given the limited observational constraints on the low-mass end of the subhalo mass function. In this talk, we will explore a novel method for finding dark subhalos by detecting stellar wakes —perturbations in the positions and velocities of stars caused by interactions with orbiting...
In the first part of this talk, I will discuss the impact of Gaia data on determining the dark matter distribution of our host galaxy, the Milky Way, presenting state-of-the-art results based on the latest data within a framework that has been tested over the past decade.
In the second part, I will introduce a recently developed machine learning method designed to infer the dark matter...
More than 80% of the matter in the Universe is made up of a substance whose nature remains one of the greatest mysteries in physics: dark matter. Although there is clear evidence of its existence and gravitational effects, no evidence has been found of dark matter interacting with Standard Model matter beyond gravity.
Astrophysical and cosmological observations serve as powerful tools to...
The method of indirect detection of Dark Matter (DM) in neutrino telescopes involves the observation of a Cherenkov light pattern left by their annihilation or decay products crossing the detector. An excess of neutrinos produced by these processes is searched in astrophysical targets such as the Galactic Centre or the Sun, where large amounts of DM are believed to accumulate. An interesting...
The annihilation of accumulated dark matter within planetary bodies could lead to observable signatures in the form of anomalous UV airglow and excess internal heat flow. We use existing UV and IR spectral data obtained by spaceprobe flybys of Solar System planets to constrain such effects. By comparing the measured spectra to potential dark matter-induced emissions, we place limits on...
With their large exposures from the heaven, celestial objects serve as natural dark matter detectors. For leptophilic dark matter, interactions with electrons inside these objects can lead to energy loss, allowing dark matter to become gravitationally bound. Using the Sun and observations by Super-Kamiokande, we set world-leading constraints on the dark matter–electron scattering cross section...
Strong first-order phase transitions offer a compelling explanation for the stochastic gravitational wave background in the nano-Hertz range measured by pulsar timing arrays (PTA). In this talk, I will consider a classically conformal dark sector in which the symmetry breaking of a dark $U(1)$ gives rise to a gravitational wave background that can fit the PTA data and additionally sources the...
I will discuss how new physics can modify the cosmological history of the Universe at the time of dark matter production, and how this can dramatically change our inference of favored parameter space and what experimental searches for dark matter can expect to see.
The astrophysical evidence for dark matter provides compelling argument for the existence of physics beyond the Standard Model. Collider experiments such as ATLAS offer the ability to search for dark matter at high energy scales and characterise its interactions, and provide complementarity probes to direct and indirect dark matter detection searches and dedicated low mass dark matter...
Many theories beyond the Standard Model (SM) have been proposed to address several of the SM shortcomings. Some of these beyond-the-SM extensions predict new particles or interactions directly accessible at the LHC, but which would leave unconventional signatures in the ATLAS detector. These unconventional signatures require special techniques and reconstruction algorithms to be developed,...
Among the intriguing scenarios of new physics that provide explanation to several shortcomings of the Standard Model (SM), hidden valley scenarios include a Dark Sector that extends the SM with a non-Abelian gauge group, similar to quantum chromodynamics with new matter and gauge fields analogous to the SM quark and gluon fields. This may result in a rich phenomenology which we can access...
Vector $U$-bosons, commonly known as 'dark photons', are hypothesized mediators of dark matter interactions. In this study, we establish a methodology to set theoretical constraints on the upper limit of the kinetic mixing parameter $\varepsilon^2(M_U)$ by analyzing dilepton spectra from heavy-ion collisions spanning SIS to LHC energies. Our approach relies on the microscopic...
The LHCb experiment searches the existence of dark photons ($A'$) as potential mediators between the Standard Model and a hypothesized dark sector, which is expected to interact feebly with Standard Model (SM) particles through kinetic mixing. Results from Run 1 and Run 2, focusing on prompt and displaced dark photon decays into muon pairs ($A'→\mu^+\mu^-$), have set world-leading exclusion...
The Belle II experiment has unique reach for a broad class of models that postulate the existence of dark matter particles with MeV—GeV masses. This talk presents recent world-leading physics results from Belle II searches for Z' bosons, axion-like particles, and dark scalars in association with two muons in e+e- collisions; long-lived (pseudo)scalars produced in decays of B-mesons; inelastic...
In the SUSY DM searches, both ATLAS and CMS show consistent excesses in two independent search channels. While each of these four searches is at the 1-2 $\sigma$ level, it is the first time that all relevant channels show these consistent excesses. These searches indicate a DM mass (of the lightest neutralino) of about 200 GeV, with two more particles (the second lightest neutralino and the...
Dark matter phenomenology in BSM models at future lepton colliders (focus on the ILC) are discussed. As an explicit example, a strategy for parameter determination of a supersymmetric DM candidate in the MSSM is presented. The importance of polarized beams and threshold scans is critically analyzed. Precision requirements of masses and cross sections are worked out and compared for the...
NA64 is a fixed target experiment at the CERN Super Proton Synchrotron accelerator searching for Dark Sectors employing high energy electron, positron and muon beams. In this talk, we report its latest results on sub-GeV Dark Matter searches with the 2016-2022 statistics. With the new data, NA64 is starting to probe for the first time the very interesting region of parameter space motivated by...
The proposed LUXE experiment (LASER Und XFEL Experiment) at DESY, Hamburg, using the electron beam from the European XFEL, aims to probe QED in the non-perturbative regime created in collisions between high-intensity laser pulses and high-energy electron or photon beams. This setup also provides a unique opportunity to probe physics beyond the standard model. In this talk we show that by...
[Connecting via Zoom] Cosmological observables, from the Lyman-alpha forest to the Milky Way substructure, offer unique avenues for probing dark matter and neutrino sectors. Moreover, they often reveal anomalies and tensions that could signal new physics. I will review the status of the recent early-universe and late-universe searches for dark matter and neutrino interactions, highlighting in...
Recent observations have revealed a Cosmic Microwave Background (CMB) temperature decrement toward local galaxies within the 2MASS Redshift Survey. We examine this detection by investigating its frequency dependence and sensitivity to component separation methods, indicating that Galactic foregrounds are unlikely responsible. Unlike previous studies, our findings show the decrement is...
Short gamma-ray bursts (GRBs) are some of the brightest transients in the universe. Heavy axion-like particles (ALPs) can be produced in the hot plasma of GRB fireballs and escape, transporting energy away the from the source. When they decay outside the source, we show that the resulting photon field is too rarefied to re-thermalize, effectively preventing the re-emergence of the fireball,...
Axion-like particles (ALPs) are compelling dark matter candidates, particularly in the "ultralight mass regime." In this talk, I will discuss the theoretical framework for ALP interactions with Standard Model fields, emphasising the renormalization group (RG) running and low-energy matching in quantum field theory. Many quantum sensor experiments are designed to probe very light ALPs, which...
The ANAIS (Annual modulation with NaI(Tl) Scintillators) experiment is intended to search for dark matter annual modulation with ultrapure NaI(Tl) scintillators in order to provide a model independent confirmation or refutation of the long-standing DAMA/LIBRA positive annual modulation signal in the low energy detection rate, using the same target and technique. Other experiments exclude the...
The signal measured by the DAMA/LIBRA experiment matches the expectations of an annually modulating signal caused by particle dark matter (DM) from the galactic halo with very high statistical significance. At the same time, this result is in strong tension with null results from many other DM direct detection experiments. These tensions, however, critically depend on assumptions about the...
SABRE is an international collaboration that will operate similar particle detectors in the Northern (SABRE North) and Southern Hemispheres (SABRE South). This innovative approach distinguishes possible dark matter signals from seasonal backgrounds, a pioneering strategy only possible with a southern hemisphere experiment. SABRE South is located at the Stawell Underground Physics Laboratory...
The MAgnetized Disk and Mirror Axion eXperiment (MADMAX) is a future experiment for the search of axion dark matter. Its detection principle is based on the conversion of axions into photons in a magnetic field. The axion to photon conversion is enhanced by a booster made of dielectric disks placed in front of a mirror. In its final version, MADMAX aims to scan the uncharted QCD axion mass...
Massive primordial black holes may accrete baryonic matter and accretion disk are expected to form around them. The radiation emitted in this process can reveal their presence both in astronomical and cosmological settings.
In order to compute realistic constraints, it is critical to understand accretion physics. In this talk I will discuss an accretion model that takes into account radiation...
A range of haloscope searches are currently probing axions in the mass range ~2-40 μeV. However, simulations of the axion field in the early Universe are increasingly pointing towards heavier masses if we want the axion to comprise all of the Dark Matter in the Universe. I will briefly review these developments and then I will present The Canfranc Axion Detection Experiment (CADEx), a proposed...
Axions or axion-like particles (ALPs) are hypothetical particles predicted by various BSM theories, which make one of the dark matter candidates. If ALPs exist in nature, the CMB photons as they pass through galaxy clusters will convert to ALPs (of mass range $10^{-11}-10^{-14}$ eV), resulting in a polarized spectral distortion in the CMB. The resonant conversions dominate over the...
