Related papers: Hot vs cold hidden sectors and their effects on th…
Dark matter may be hidden, with no standard model gauge interactions. At the same time, in WIMPless models with hidden matter masses proportional to hidden gauge couplings squared, the hidden dark matter's thermal relic density may…
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…
A variety of supergravity and string based models contain hidden sectors which can play a role in particle physics phenomena and in cosmology. In this note we discuss the possibility that the visible sector and the hidden sectors in general…
We consider dark matter as Strongly Interacting Massive Particles (SIMPs) in a hidden sector, thermally decoupled from the Standard Model heat bath. Due to its strong interactions, the number-changing processes of the SIMP lead to its…
In the standard thermal relic scenario, dark matter remains in chemical equilibrium with the Standard Model radiation bath until freeze-out occurs at $T \sim m_X/20$, where $m_X$ is the dark matter mass. In this familiar class of models,…
If, during the early Universe epoch, the dark matter particle thermalizes in a hidden sector which does not thermalize with the Standard Model thermal bath, its relativistic thermal decoupling can easily lead to the observed relic density,…
We investigate the thermal relics as hot, warm and cold dark matter in $\mathscr{L}=\varepsilon^{2-2\beta}R^\beta+{16\pi}m_{\text{Pl}}^{-2}\mathscr{L}_m$ gravity, where $\varepsilon$ is a constant balancing the dimension of the field…
We study models in which the inflaton is coupled to two otherwise decoupled sectors, and the effect of preheating and related processes on their energy densities during the evolution of the universe. Over most of parameter space, preheating…
We have developed a set of four fully coupled Boltzmann equations to precisely determine the relic density and temperature of dark matter by including three distinct sectors: dark matter, light scalar, and standard model sectors. The…
We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard…
The secluded dark matter resides within a hidden sector and self-annihilates into lighter mediators which subsequently decay to the Standard Model (SM) particles. Depending on the coupling strength of the mediator to the SM, the hidden…
We study the thermodynamic history of composite Dark Matter models. We start with classifying the models by means of the symmetries partially protecting the composite Dark Matter decays and constrain their lifetimes. For each model, we…
If the interaction rates between the visible and the dark sectors were never strong enough, the observed dark matter relic abundance could have been produced in the early Universe by non-thermal processes. This is what occurs in the…
The decoupling of a cold relic, during a decaying-particle-dominated cosmological evolution is analyzed, the relic density is calculated both numerically and semi-analytically and the results are compared with each other. Using plausible…
We study the effect of the elastic scattering on the non-thermal WIMP, which is produced by direct decay of heavy particles at the end of reheating. The non-thermal WIMP becomes important when the reheating temperature is well below the…
Biswas et al. found that the thermal relic density of a dark matter particle freezing out while the universe's energy density is dominated by a non-standard extra component $\phi$, whose energy density redshifts faster than radiation, can…
Dark matter (DM) as a thermal relic of the primordial plasma is increasingly pressured by direct and indirect searches, while the same production mechanism in a decoupled sector is much less constrained. We extend the standard treatment of…
We consider dark matter consisting of weakly interacting massive particles (WIMPs) and revisit in detail its thermal evolution in the early universe, with a particular focus on models where the annihilation rate is enhanced by the…
Cosmologically stable, light particles that came into thermal contact with the Standard Model in the early universe may persist today as a form of hot dark matter. For relics with masses in the eV range, their role in structure formation…
In this work, we investigate a scenario in which heavy Majorana Right-Handed Neutrinos (RHNs) are in thermal equilibrium with a dark sector with temperature higher than the Standard Model (SM) thermal bath. Specifically, we consider the…