A short address from Carlos Beltrán, Vice-Rector for Research and Scientific Policy at the University of Cantabria
To the date, the only positive signal of presence of dark matter (DM) in the Milky Way halo by direct observation of its interaction with a detector comes from the DAMA/LIBRA experiment in the Gran Sasso National Laboratory (LNGS). For more than 20 years it has observed an annual modulation in the low energy counting rate compatible with that expected due to the rotation of the Earth around...
For a fully model-independent investigation of the nature of the DAMA/LIBRA signal, experiments which use the same material as DAMA/LIBRA are mandatory.
COSINUS will use crystals of NaI, however not operating them as mere scintillation detectors, but as so-called cryogenic scintillating calorimeters cooled to milli-Kelvin temperatures. COSINUS detectors provide a simultaneous and independent...
The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional...
The XENONnT detector is the latest in the series of XENON experiments, utilizing the concept of dual-phase time projection chambers (TPCs) for the direct detection of weakly interacting massive particles (WIMPs). Located at the INFN Gran Sasso National Laboratory in Italy, the detector was commissioned in 2021 and has already completed its first science run. With an increased liquid xenon...
Dark photon dark matter in the milli-eV mass range is notoriously difficult to detect, being too high in frequency for high-$Q$ cavity resonators yet below the energy threshold of single-photon detectors. I will present a new method that overcomes this difficulty, based on recent work (arXiv:2208.06519) with Peter Graham and Gerald Gabrielse et al. We propose to use trapped electrons as...
I explore the possibility of dark matter being composed of stable scalar glueballs from a confining dark SU(N) gauge theory. The relic abundance of these glueballs is studied for the first time in a thermal effective theory, using an effective potential fitted by lattice simulations. The predicted relic abundance is smaller than previously believed. Moreover, this framework can be easily...
Hidden sectors provide a simple explanation for the origin of dark matter. What is the symmetry of such a hidden sector? One possibility is that the hidden sector is related to the Standard Model gauge group via a discrete or "mirror" symmetry. Such a Mirror Standard Model has three main advantages: 1) It provides a natural dark matter candidate in the lightest stable mirror particle, namely...
Many models of Dark Matter (DM) have been proposed to accommodate the overwhelming evidence from cosmological and astrophysical sources. One popular category of such models are simplified models, which extend the Standard Model (SM) with a singlet DM particle and a mediator as a portal to the SM. In this talk I will present the results of various global fits of simplified models of DM, in...
Axions are hypothetical elementary particles with their small masses and tiny couplings to matter sectors, and they are known as the promising candidates for the dark matter in our Universe. Axions generically couple to the photon via the chiral anomaly effect and differentiate the phase velocities between two circularly-polarized photons, which leads to a rotation of photon's polarization...
When coupled to electromagnetism via a Chern-Simons interaction, axion-like particles (ALP) produce a rotation of the plane of linear polarization of photons known as cosmic birefringence. Recent measurements of cosmic birefringence obtained from the polarization of the cosmic microwave background (CMB) hint at the existence of an isotropic birefringence angle of $\beta\approx0.3^\circ$....
Dark matter interactions with Standard Model particles can inject energy at early times, altering the standard evolution of the early universe. In particular, this energy injection can perturb the spectrum of the cosmic microwave background (CMB) away from that of a perfect blackbody and affect processes by which the first stars form. For this study, I will discuss recent work to update the...
We compare the latest JWST deep observations with semi-analytic galaxy formation models. We observe a clear break in the slope of the number counts. This break is more pronounced at longer wavelengths. Since our model is able to reproduce this wavelength-dependent feature very well, we investigate how this could be related to the merging history of galaxies which in turn is sensitive to the...
The distribution of matter within dark matter halos contains key information about the nature and the properties of dark matter. Knowledge of the exact local dark matter density is not only important for cosmology, but also essential for precise calculations in both direct and indirect detection experiments. Getting the most out of the simulations from which the density profiles are inferred...
In a confining extension to the Standard Model, a stable composite particle could be a viable dark matter candidate. Often referred to as a strongly-interacting dark sector, such a theory along with a portal to the Standard Model can give rise to interesting semi-visible jet signatures at particle colliders. However, we still have a lot of work to do in improving our understanding of the...
Using a simplified mechanical-Lagrangian model we describe the gravitational waveform during the last seconds of the BNS merger phases in a dark matter environment. By considering
characteristic magnitudes for Neutron Stars from existing numerical simulations and magnitudes measurable during the BNS inspiral phase, i.e, chirp mass, mass ratio and distance we explore the effective parameter...
Unveiling the true nature of Dark Matter (DM), which manifests itself only through gravity, is one of the principal quests in physics. Leading candidates for DM are weakly interacting massive particles (WIMPs) or ultralight bosons (axions), at opposite extremes in mass scales,that have been postulated by competing theories to solve deficiencies in the Standard Model of particle physics....
In the fuzzy dark matter model, dark matter consists of “axion-like” ultra-light scalar particles with a mass of around $10^{-22}$ eV. This candidate behaves similarly to cold dark matter on large scales, but exhibits different properties on smaller (galactic) scales due to macroscopic wave effects arising from the extremely light particles’ large de Broglie wavelengths. It has both particle...
In simulations of galaxy formation, dark matter is typically modeled as a cold, collisionless particle that interacts solely through the force of gravity. This is an excellent approximation in many aspects of structure formation, but discrepancies remain between predictions and observations especially in the density profile shape of various sizes of dark matter halos. Such discrepancies may...
The talk will cover the latest searches for DM at LHC, with particular emphasis on the benchmark models used in the ongoing searches,
including Higgs portal models, simplified models with s and t-channel mediators and models with extended Higgs and gauge sectors.
Prospects for DM searches in Run-3 will also be discussed.
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...
Evidence for Dark Matter particles arising from direct searches has proven to be extremely elusive. An alternative approach to probing the dark sector is to search for new force carriers which can interact with Standard Model particles. A theoretically well-motivated model has proposed the presence of a new U(1) gauge boson, the heavy photon A', which might be a mediator between light thermal...
HUNTER (Heavy Unseen Neutrinos from Total Energy-momentum Reconstruction) is a future experiment that will search for additional “sterile” neutrinos beyond the Standard Model (BSM) using an instrument for radioactive atom trapping and high-resolution decay product spectrometry. HUNTER will be a concise experimental test for the existence of a sterile neutrino with masses between a 10-100 keV...
Using a novel 3D modeling approach, we determined the properties of the dark-matter halo of a dozen star-forming galaxies. We find that a significant fraction of the sample shows cored dark-matter profiles over the LCDM expectations (NFW). In addition, the cuspiness of the DM profiles is found to be a strong function of the recent star-formation activity. We will discuss on going work, new...
According to the LambdaCDM cosmology, present-day galaxies with stellar masses M>10^11 M_sun should contain a sizable fraction of dark matter within their stellar body. Models indicate that in massive early-type galaxies (ETGs) with M~1.5x10^11 Msun dark matter should account for ~15% of the dynamical mass within one effective radius (1 R_e) and for ~60% within 5 R_e. Most massive ETGs have...
Dark matter (DM) may be comprised of axionlike particles (ALPs) with couplings to photons and the standard model fermions. We study photon signals arising from cosmic ray (CR) electron scattering on background ALPs. For a range of masses we find that these bounds can place competitive new constraints on the ALP-electron coupling. In addition to current Fermi constraints, we also consider...
Particle physics today faces the challenge of explaining the mystery of dark matter, the
origin of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent fine-tuning of the electro-weak scale, and many other aspects of fundamental physics. Perhaps the most striking frontier to emerge in the search for answers involves new physics at mass scales comparable to...
Searches in CMS for dark matter in final states with invisible particles recoiling against visible states are presented. Various topologies and kinematic variables are explored, including jet substructure as a means of tagging heavy bosons. In this talk, we focus on the recent results obtained using the full Run-II dataset collected at the LHC.
New physics may have gone unseen so far at the LHC 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. The analyses are based on proton-proton collision data corresponding to an integrated luminosity of...
Collider searches for dark matter (DM) so far have mostly focussed on scenarios where DM particles are produced in association with heavy standard model (SM) particles or jets. However, no deviations from SM predictions have been observed. Several recent phenomenology papers have proposed models that explore the possibility of accessing the strongly coupled dark sector, giving rise to unusual...
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 Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric 0νββ experiment to reach the one-tonne mass scale. The detector, located underground at the Laboratori Nazionali del Gran Sasso in Italy, consists of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers, operating at a base temperature of about 10 mK. After beginning its first physics...
The QCD axion is a promising dark matter candidate whose discovery would also solve the Strong CP problem of particle physics. The DMRadio suite of experiments, which consists of DMRadio-50L, DMRadio-m3, and DMRadio-GUT, are designed to be sensitive to QCD axions in the peV to ueV mass range. Axions in this mass range may be produced in the measured dark matter abundance in the early universe...
Cosmological and astrophysical observations provide a unique opportunity to probe the fundamental properties of dark matter. Dark matter interactions with the Standard Model of particle physics, for example, can alter predictions from the standard cosmological model, permitting robust tests of new dark matter physics. In this talk, I will describe the effects of dark matter elastic scattering...
The flux of high-energy astrophysical γ rays is attenuated by the production of electron-positron pairs from scattering off of extragalactic background light (EBL). We use the most up-to-date information on galaxy populations to compute their contributions to the pair-production optical depth. We find that the optical depth inferred from γ-ray measurements exceeds that expected from galaxies...
Compact stars due to their enormous gravitational field can accumulate a sizable amount of dark matter in their interior. Depending on its nature, accumulated dark matter may affect the properties of neutron stars in quite different ways. I will give an overview of the impact of dark matter on various observable properties of neutron stars, i.e. the mass-radius relation, tidal deformability,...
Direct dark matter detection experiments can reach the thresholds as low as O(10eV). In that regime, we report precision ionization measurements induced by Compton scattering of gamma rays and nuclear recoils from neutrons. A skipper charge-coupled device (CCD) with single electron resolution developed for DAMIC-M experiment was used to collect data. Compton scattering on sil- icon atomic...
The CYGNO collaboration aims to propose a large volume (O(30m^3)) gaseous Time Projection Chamber (TPC) with optical readout to search for rare events, such as interactions of DM in the GeV mass range and solar neutrinos. The TPC, operated with a He:CF4 gas mixture at atmospheric pressure, uses a triple Gas Electron Multiplier (GEM) stack to amplify primary ionization charges and produce...
Dark photons have been well motivated as strong candidates for dark force carriers and light dark matter in the sub-GeV mass range. Fixed-target experiments as a promising complementary approach to the collider could have good sensitivity in the low mass range. We would present the proposed study of Dark SHINE experiment searching for dark photon produced via electron-nucleon interaction and...
Global analyses of different dark matter searches are necessary to determine the status of dark matter models. Highly accurate antiproton measurements from AMS-02 would add valuable information to such global analyses. I will present an analysis pipeline for fast and accurate antiproton likelihoods in global scans. The pipeline consists of a neural network emulator for antiproton flux...
Radio observations can provide useful information about the nature of dark matter: axion line, etc. In this talk, I will briefly review the relevant dark matter phenomenology in these frequencies and present fresh results from the stacked analysis of six dwarf spheroidal galaxies by the LOw Frequency ARray (LOFAR). This is the first time such an analysis has been carried out using LOFAR data....
Prompt cusps are the densest quasi-equilibrium dark matter objects; one forms at the instant of collapse within every isolated peak of the initial cosmological density field. They have power-law density profiles, ρ∝r−1.5 with central phase-space density set by the primordial velocity dispersion of the dark matter. At late times they account for ∼1% of the dark matter mass but for >90% of its...
Galaxy clusters are dark-matter-dominated systems enclosed in a volume that is a high-density microcosm of the rest of the universe. I will present the most recent results on the distribution of their gravitating and baryonic mass obtained from our XMM-Newton Multi-year Heritage and Large Programmes complemented with Planck maps (CHEX-MATE, X-COP), highlighting the role of X-ray and SZ data in...
While the experimental program to directly detect light dark matter is proceeding full steam ahead, the theoretical one is at a crossroads. I will review the status of both, highlighting the obstacles theories of sub-GeV dark matter must overcome. I will detail two such benchmarks future direct detection experiments will explore.
The DAMIC-M (DArk Matter In CCDs at Modane) experiment employs a novel technique to search for the elusive particles which make up most of the matter in the universe, called dark matter. The aim is direct detection of light dark matter (WIMPs, Hidden Sector Particles) via interaction with silicon in the bulk of the CCDs (Charged Coupled Devised). These CCDs use skipper amplifiers to...
We present the latest results of the low mass dark matter searches with the DarkSide-50 experiment. DarkSide-50 is a dual phase Time Projection Chamber based on low radioactivity argon. The full (12202 ± 180) kg * day dataset collected from 2015 to 2018 underground at the Laboratori Nazionali del Gran Sasso has been recently analyzed. In addition to the usual frequentist analysis, a Bayesian...
The LUX-ZEPLIN (LZ) dark matter search experiment, a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA, has the world's leading sensitivity to searches for Weakly Interacting Massive Particles (WIMPs). It is comprised of a 10-tonne target mass (7-tonne active) and outfitted with photomultiplier tubes in both the central...
An overview of QCD-like strongly interacting dark matter.
We employ a non-relativistic effective theory to model dark matter (DM) induced electron ejections from graphene and carbon nanotubes (CNTs), materials currently in the R&D phase for direct detection experiments. The material properties of graphene are modelled using Density Functional Theory, and we obtain observable ejection rates for arbitrary forms of scalar and spin-1/2 DM. We show how...
The direct detection of sub-GeV dark matter particles is a major experimental challenge. In this low energy range, the energy transfer between sub-GeV particles and a solid target media is only in the range of a few millielectron-volts to a few electron-volts, which dares the current capabilities of sensors. However, the application of state-of-the-art developments in quantum information...
The QUAX experiment is committed in the search of light dark matter candidates, such as axions and axion-like particles, with a haloscope setup involving microwave resonant cavities. Many avenues to push further the haloscope sensitivity are being tested, facing some technological challenges. One of these is the development of superconducting cavities and dielectric cavities, showing...
Observational constraints have closed off all but one mass-window for primordial black holes making up all of the dark matter, and there are some specific conditions required for their production in the first place. However, they remain a tantalising dark matter candidate because they require no new beyond the standard model particles and they would additionally provide a lot of information...
Caustic crossing events of stars in galaxies lensed by galaxy clusters can lead to extreme magnification factors, $\mu > 1000$. Several stars at cosmological redshifts, $z > 1$, have already been observed by the Hubble Space Telescope, and the number is rapidly increasing with the Jame Webb Space Telescope. The probability distribution of magnification depends on the galaxy cluster and the...
The first stars in the Universe, soon to be observed with the James Webb Space Telescope (JWST) can be extremely powerful Dark Matter (DM) probes. If DM does not play a significant role in the formation of some of the first stars, then, zero metallicity Hydrogen burners (Population III stars) form. Conversely, for scenarios where DM plays a significant role during the formation of a star from...
Strong gravitational lensing by galaxies provides us with a powerful laboratory for testing dark matter models. Various particle models for dark matter give rise to different small-scale distributions of mass in the lens galaxy, which can be differentiated if the observation is sensitive enough. The sensitivity of a gravitational lens observation to the presence (or absence) of low-mass dark...
There are several well-motivated scenarios in which dark matter could be present around black holes at a sufficient level to impact on the gravitational waveform of a merger. However, developing templates for the impact of such environments is challenging - in particular one issue that requires more attention is how to select and impose appropriate initial conditions that represent the state...
Ultralight dark matter is an exciting alternative to the standard cold dark matter paradigm, reproducing its large scale predictions, while solving most of its potential tension with small scale observations (like the "cusp-core" and "missing satellites" problems). If dark matter is made of some new light scalar particle, relatively dense and large structures are expected to form at the center...
Old isolated neutron stars have been gathering attention as targets to probe Dark Matter (DM) through temperature observations. DM will anomalously heat neutron stars through its gravitational capture and annihilation process, which predicts $T_s \simeq (1-3) \times 10^3$ K for $t > 10^{6}$ years. We may put constraints on DM-nucleon scattering cross section by finding even colder neutron...
The observed dark matter relic abundance may be explained by different mechanisms, such as thermal freeze-out/freeze-in, with one or more symmetric/asymmetric components. In this work we investigate the role played by asymmetries in determining the yield and nature of dark matter in scenarios with more than one dark matter particle. In particular, we show that the energy density of a particle...
WIMP particles down to MeV-scale masses can be thermal relic dark matter candidates, provided they fulfill two requirements. These dictate what kind of models can realise them.
First, to have a sufficiently large annihilation rate in the early Universe, a new light mediator particle coupled to the light SM degrees of freedom is necessary. Due to the chiral structure of the SM, the number of...
We consider the phenomenological nightmare scenario where dark matter is only coupled gravitationally, thinking of black holes as probes. We choose to focus on wave dark matter because an oscillating massive scalar endows a black hole with hair, whose profile we study.
We examine some assumptions implicit in the existing literature, and we do so by taking a fully analytic approach. We...
A cosmic string-wall network is associated with the breaking of a U(1) global symmetry into a discrete Z(N) symmetry with N>1. Its annihilation due to a small bias between the N minima is accompanied by “catastrogenesis” (from the greek for annihilation), the production of pseudo-Goldstone bosons (pGBs) - e.g. axions, ALPs, or majorons - gravitational waves, and primordial black holes...
We present the design, status and first results of a detector to search for axions and axion-like particles in the galactic halo using laser interferometry enhanced via squeezed states of light. The detector is sensitive to the polarisation rotation of linearly polarised light induced by an axion field in the mass range from 10^−16 eV up to 10^−8 eV, and is likely to significantly surpass the...
