Related papers: Coherent relaxion dark matter
Motivated by their potential role as dark matter, we study the cosmological evolution of light scalar and vector fields non-minimally coupled to gravity. Our focus is on a situation where the dominant contribution to the energy density…
The observed tightness of the mass discrepancy-acceleration relation (MDAR) poses a fine-tuning challenge to current models of galaxy formation. We propose that this relation could arise from collisional interactions between baryons and…
The values of the Hubble constant ($\rm{H_0}$) inferred from the cosmic microwave background (CMB) and local measurements via the distance ladder exhibit a $\sim5\sigma$ tension. In this work we propose that the tension might be partially…
We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…
Assuming axions are potential dark matter (DM) candidate that make up all of the DM abundance, we discuss production of axions via (i) standard misalignment mechanism during the period of reheating and (ii) graviton-mediated 2-to-2…
We present a model with dark matter in an anomaly-mediated supersymmetry breaking hidden sector with a U(1)xU(1) gauge symmetry. The symmetries of the model stabilize the dark matter and forbid the introduction of new mass parameters. As a…
Traditional computations of the dark matter (DM) relic abundance, for models where attractive self-interactions are mediated by light force-carriers and bound states exist, rely on the solution of a coupled system of classical on-shell…
We perform an analysis of Higgs portal models of dark matter (DM), where DM is light enough to contribute to invisible Higgs decays. Using effective field theory we show that DM can be a thermal relic only if there are additional light…
We show that moderate energy relaxation in the formation of dark matter halos invariably leads to profiles that match those observed in the central regions of galaxies. The density profile of the central region is universal and insensitive…
Recently it was shown that dark matter with mass of order the weak scale can be charged under a new long-range force, decoupled from the Standard Model, with only weak constraints from early Universe cosmology. Here we consider the…
In a usual dark matter (DM) model without a huge mass difference between the DM and lighter mediator, using the coupling strength suitable for having the correct relic density, the resulting self-interaction becomes several orders of…
The cosmic-ray (CR) $e^\pm$ excess observed by AMS-02 can be explained by dark matter (DM) annihilation. However, the DM explanation requires a large annihilation cross section which is strongly disfavored by other observations, such as the…
We present a comprehensive study of secluded dark matter (DM) $\chi$, where the relic abundance is set by annihilations into lighter dark mediators $\phi$ that couple only feebly to the Standard Model (SM). In contrast to canonical WIMPs,…
We consider a simple class of models in which the relic density of dark matter is determined by the baryon asymmetry of the universe. In these models a $B - L$ asymmetry generated at high temperatures is transfered to the dark matter, which…
We investigate the viability of a simple dark matter (DM) model consisting of a single fermion in the context of galactic dynamics. We use a consistent approach that does not presume a particular DM density profile but instead requires that…
We analyze the dark matter problem in the context of brane cosmology. We investigate the impact of the non-conventional brane cosmology on the relic abundance of non-relativistic stable particles in high and low reheating scenarios. We show…
The inert doublet model, a minimal extension of the Standard Model by a second Higgs doublet, is one of the simplest and most attractive scenarios that can explain the dark matter. In this paper, we demonstrate the existence of a new viable…
A family of simple and minimal extensions of the standard cosmological $\Lambda$CDM model in which dark matter experiences an additional long-range scalar interaction is demonstrated to alleviate the long lasting Hubble-tension while…
A new relaxion mechanism is proposed where a small electroweak scale is preferably selected earlier than the larger one due to a potential instability, which is different from previously proposed stopping mechanisms by either Hubble…
The freeze-in mechanism for dark matter (DM) requires extremely feeble interactions with the Standard Model (SM), preventing thermal equilibrium in the early Universe and typically evading experimental detection. However, for sufficiently…