相关论文: Dynamical Dark Matter from Thermal Freeze-Out
We perform a model independent study of freeze-in of massive particle dark matter (DM) by adopting an effective field theory framework. Considering the dark matter to be a gauge singlet Majorana fermion, odd under a stabilising symmetry…
We discuss the energy density,temperature and entropy of dark matter (DM) and dark energy (DE) as functions of the scale factor $a$ in an expanding universe. In a model of non-interacting dark components we repeat a derivation from…
We present a model of weak scale Dark Matter (DM) where the thermal DM density is set by the lepton asymmetry due to the presence of higher dimension lepton violating operators. In these models there is generically a separation between the…
Early decoupling of thermally produced dark matter particles due to feeble interactions with the surrounding plasma typically results in their excessive abundance. In this work we propose a simple mechanism for dark matter depopulation. It…
We discuss the possibility of realising a two-component dark matter (DM) scenario where the two DM candidates differ from each other by virtue of their production mechanism in the early universe. One of the DM candidates is thermally…
We present a new paradigm for the production of dark-matter particles called the spontaneous freeze out, in which the decoupling from the thermal bath is enforced by the sudden increase of the dark-matter mass, due to the spontaneous…
We investigate a cosmological model in which a fraction of the dark matter is atomic dark matter (ADM). This ADM consists of dark versions of the electron and of the proton, interacting with each other and with dark photons just as their…
Fuzzy Dark Matter (FDM) has recently emerged as an interesting alternative model to the standard Cold Dark Matter (CDM). In this model, dark matter consists of very light bosonic particles with quantum mechanical effects on galactic scales.…
Thermal freeze-out is a compelling framework for naturally generating the dark matter abundance. We systematically study a broad range of dark matter and mediator particle combinations that can viably realize thermal freeze-out, focusing on…
We propose a scenario that explains the comparable abundances of dark matter (DM) and baryons without any coincidence in the corresponding particle masses. Here, DM corresponds to heavy "dark baryons" in a hidden MSSM-like dark sector,…
We consider the possibility that thermalized dark-matter particles acquire their mass thanks to the spontaneous breaking of a symmetry below some critical temperature. We describe the regime where a freeze out mechanism takes place shortly…
We perform a comprehensive study of models of dark matter (DM) in a Universe with a non-thermal cosmological history, i.e with a phase of pressure-less matter domination before the onset of big-bang nucleosynethesis (BBN). Such cosmological…
It has recently been shown that if the dark matter is in thermal equilibrium with a sector that is highly decoupled from the Standard Model, it can freeze-out with an acceptable relic abundance, even if the dark matter is as heavy as ~1-100…
Decaying dark matter (DDM) is a candidate which can solve the discrepancies between predictions of the concordance $\Lambda$CDM model and observations at small scales such as the number counts of companion galaxies of the Milky Way and the…
Dark matter may be coupled to dark radiation: light degrees of freedom that mediate forces between dark sector particles. Cosmological constraints favor dark radiation that is colder than Standard Model radiation. In models with fixed…
Large classes of dark sector models feature mass scales and couplings very different from the ones we observe in the Standard Model (SM). Moreover, in the freeze-in mechanism, often employed by the dark sector models, it is also required…
Asymmetric Dark Matter (ADM) models invoke a particle-antiparticle asymmetry, similar to the one observed in the Baryon sector, to account for the Dark Matter (DM) abundance. Both asymmetries are usually generated by the same mechanism and…
We describe a simple dark sector structure which, if present, has implications for the direct detection of dark matter (DM): the Dark Sink. A Dark Sink transports energy density from the DM into light dark-sector states that do not…
Well known scaling laws among the structural properties of the dark and the luminous matter in disc systems are too complex to be arisen by two inert components that just share the same gravitational field. This brings us to critically…
We propose a new mechanism where a multi-component dark sector generates the observed dark matter abundance and baryon asymmetry and thus addresses the coincidence between the two. The thermal freeze-out of dark matter annihilating into…