Related papers: Dark Matter Freeze-out During Matter Domination
Decaying dark matter models generically modify the equation of state around the time of dark matter decay, and this in turn modifies the expansion rate of the Universe through the Friedmann equation. Thus, a priori, these models could solve…
Our ignorance of the period between the end of inflation and the beginning of Big Bang Nucleosynthesis limits our understanding of the origins and evolution of dark matter. One possibility is that the Universe's energy density was dominated…
Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…
Most of our knowledge of the universe has been obtained from the anisotropy spectrum of the cosmic microwave background and observations of large-scale structures. During the history of the Universe, neutrinos from the early Universe evolve…
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…
A thermally decoupled hidden sector of particles, with a mass gap, generically enters a phase of cannibalism in the early Universe. The Standard Model sector becomes exponentially colder than the hidden sector. We propose the Cannibal Dark…
In some scenarios for the early universe, non-relativistic thermal dark matter chemically decouples from the thermal environment once the temperature drops well below the dark matter mass. The value at which the energy density freezes out…
The generation of a kination-dominated phase by a quintessential exponential model is investigated and the parameters of the model are restricted so that a number of observational constraints (originating from nucleosynthesis, the present…
The nature of dark matter (DM) remains one of the most important unanswered questions in particle physics. Here, we propose a novel scenario for DM in which weakly interacting massive particles (WIMPs) can freeze-in due to a first-order…
Dark matter, $X$, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature $T_R \ll {\rm TeV}$. Compared to the conventional radiation-dominated (RD) results, yields from both…
Within the standard cosmological scenario the Universe is found to be filled by obscure components (dark matter and dark energy) for ~95% of its energy budget. In particular, almost all the matter content in the Universe is given by dark…
The inclusion of a period of (effective) matter domination following inflation and prior to the onset of radiation domination has interesting and observable consequences for structure growth. During this early matter-dominated era (EMDE),…
We consider the production of dark matter during the process of reheating after inflation. The relic density of dark matter from freeze-in depends on both the energy density and energy distribution of the inflaton scattering or decay…
We investigate the thermal relic density of the cold dark matter in the context of the brane world cosmology. Since the expansion law in a high energy regime is modified from the one in the standard cosmology, if the dark matter decouples…
We investigate a model of the universe where dark energy is replaced by electrically-charged extremely-massive dark matter. This was originally described only for the present cosmological time. The time dependence of the charged dark matter…
As the early universe expands and cools the rates of the weak interactions that keep neutrinos in thermal equilibrium with the matter and the related rates of the reactions that inter-convert neutrons and protons decrease. Eventually, these…
Conversion-driven freeze-out is an appealing mechanism to explain the observed relic density while naturally accommodating the null-results from direct and indirect detection due to a very weak dark matter coupling. Interestingly, the…
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…
The South Pole Telescope (SPT), Atacama Cosmology Telescope (ACT), and Wilkinson Microwave Anisotropy Probe (WMAP) have each reported measurements of the cosmic microwave background's (CMB) angular power spectrum which favor the existence…
The low velocity part of a kinetic equilibrium dark matter distribution has higher phase space density and is more easily incorporated in formation of a low mass galaxy than the high velocity part. For relativistically decoupling fermions…