Cosmic ray antiprotons are among the best channels to constrain WIMP dark matter particle candidates. The compatibility of AMS-02 data with a pure secondary origin is currently actively debated. Using the USINE code and an improved methodology to extract the cosmic ray transport parameters from the B/C data, we derive a robust range of predictions for the secondary antiproton flux. We list and...
X-ray line searches are sensitive probes for many dark matter models, such as sterile neutrino dark matter in the nuMSM. I will discuss the current status of the experimental efforts, including that of the tentative signal at 3.5 keV. Then I will discuss some recent progress with NuSTAR and its prospects in the near future. Finally, I will talk about the idea of dark matter velocity...
Observational constraints on gamma rays produced by the annihilation of weakly interacting massive particles around primordial black holes (PBHs) imply that these two classes of Dark Matter candidates cannot coexist. In this talk, I will show that the successful detection of one or more PBHs by radio searches (with the Square Kilometer Array) and gravitational waves searches (with LIGO/Virgo...
To constrain the contribution of source populations to the observed neutrino sky, we consider isotropic and anisotropic components of the diffuse neutrino data. We simulate through-going muon neutrino events by applying statistical distributions for the fluxes of extra-galactic sources and investigate the sensitivities of current (IceCube) and future (IceCube-Gen2 and KM3NeT) experiments. I...
We propose a multi-messenger probe of the natural parameter space of QCD axion dark matter (DM) based on observations of black hole-neutron star binary inspirals. It is suggested that a dense DM spike may grow around intermediate mass black holes. The presence of such a spike produces two unique effects: a distinct phase shift in the gravitational wave strain during the inspiral period and an...
GUM is a new feature of the GAMBIT global fitting software framework, which provides a direct interface between Lagrangian level tools and GAMBIT. GUM automatically writes GAMBIT routines to compute observables and likelihoods for physics beyond the Standard Model. I will describe the structure of GUM, the tools (within GAMBIT) it is able to create interfaces to, and the observables it is able...
Paleo-detectors are a proposed experimental technique in which one would search for traces of recoiling nuclei in ancient minerals. Natural minerals on Earth are as old as $\mathcal{O}(1)\,$Gyr and, in many minerals, the damage tracks left by recoiling nuclei are also preserved for time scales long compared to $1\,$Gyr once created. Thus, even reading out relatively small target samples of...
DAMIC (for Dark Matter In CCD) seeks for DM interaction in thick fully depleted CCDs. Thanks to the precise energy estimation, the granularity and the very low noise of these detectors, DAMIC is sensitive to low mass WIMP (below 10GeV/c^2) through nuclear recoil but also to hidden sector model through interaction of DM particles with electrons. DAMIC at Snolab, a version of DAMIC experiment...
The DarkSide experiment is designed for the direct detection of WIMPs by means of a double phase liquid argon TPC, inserted inside a double system of active vetoes. The current detector, DarkSide-50, is running with a 50 kg fiducial mass underground argon fill.
The results of DarkSide-50 will be discussed before presenting the larger 20 tonnes project, DarkSide-20k.
The EDGES low-band experiment has measured an absorption feature in the cosmic microwave background radiation (CMB), corresponding to the 21 cm hyperfine transition of hydrogen at redshift z simeq 17, before the era of cosmic reionization. The amplitude of this absorption is connected to the ratio of singlet and triplet hyperfine states in the hydrogen gas, which can be parametrized by a spin...
In electroweak baryogenesis the baryon asymmetry of the universe is created during a first-order electroweak phase transtion. The scenario requires new physics at the electroweak scale, in particular an extended Higgs sector and new sources of CP violation, which can be tested experimentally. It would be advantageous if the crucial aspects of the various models can be tested in a single...
Many string compactifications predict the existence of a scalar field (modulus) with a mass of 100-10000 TeV. In the early universe its decay (at MeV-temperatures) generates large amounts of entropy and washes out any previously produced baryon asymmetry. I describe how the baryon asymmetry can be (re)generated by the modulus decay. The mechanism relates the smallness of the asymmetry to the...
We study the spectrum of gravitational waves produced by a first order phase transition in a hidden sector that is colder than the visible sector. In this scenario, bubbles of the hidden sector vacuum can be nucleated through either thermal fluctuations or quantum tunnelling. If a cold hidden sector undergoes a thermally induced transition, the amplitude of the gravitational wave signal...
Within the framework of ΛCDM, the local determination of the Hubble constant disagrees -- at the 4.4 sigma level -- with that inferred from the very accurate CMB observations by the Planck satellite. This clearly motivates the study of extensions of the standard cosmological model that could reduce such tension. Proposed extensions of ΛCDM that reduce this so-called Hubble tension require an...
The central measured Standard Model parameters indicate that, at large scale, the Higgs potential develops a second minimum at energy lower than the current Electroweak vacuum.
This has important consequence for cosmology. For instance, the dynamics of the Higgs during inflation could have triggered the decay of the EW vacuum with fatal consequences for our Universe. By requiring that this...
The stochastic gravitational-wave background (SGWB) is formed from the incoherent superposition of many GW sources throughout cosmic history. I will briefly summarise the astrophysical and cosmological sources that contribute to the SGWB and the ongoing searches by cross-correlating data between multiple GW detectors. I will review the current limits on the SGWB and the consequences for...
The observation of Gravitational Waves (GWs) has opened up a whole new avenue for constraining and detecting particle Dark Matter (DM). One of the most promising systems to study is the Intermediate Mass Ratio Inspiral (IMRI): a stellar-mass compact object such as a black hole or neutron star inspiraling towards an intermediate mass black hole, thousands of times more massive than the Sun....
Ultra light axion fuzzy dark matter (FDM) has recently risen as a topical alternative that solves some of the galactic scale problems associated CDM-based structure formation. The long de Broglie wavelength leads for example to constant density cores replacing the density cups at the centres of CDM haloes.
This same property however also leads to interference patterns and accompanying...
