Related papers: Thermalizing sterile neutrino dark matter
Sterile neutrinos are one of the leading dark matter candidates. Their masses may originate from a vacuum expectation value of a scalar field. If the sterile neutrino couplings are very small and their direct coupling to the inflaton is…
We present a mechanism for producing a cosmologically-significant relic density of one or more sterile neutrinos. This scheme invokes two steps: First, a population of "heavy" sterile neutrinos is created by scattering-induced decoherence…
In usual particle models, sterile neutrinos can account for the dark matter of the Universe only if they have masses in the keV range and are warm dark matter. Stringent cosmological and astrophysical bounds, in particular imposed by X-ray…
Neutrino-neutrino interactions, as mediated by standard model Z exchange, can drastically enhance the Dodelson-Widrow mechanism for the production of sterile neutrinos in the region of temperature $5-15$MeV. For a sterile mass in the KeV…
One of the promising dark matter (DM) candidates is a keV scale sterile neutrino. In the early universe the observed relic of the sterile neutrino DM is generated via the \textit{Dodelson-Widrow} mechanism. However, this production scenario…
Taken at face value, current experimental data indicate the existence of a new particle, the sterile neutrino, which must be a singlet under the Standard Model gauge group. Although they are not detectable through traditional means, such…
The expansion history and thermal physical process that happened in the early Universe before big bang nucleosynthesis (BBN) remains relatively unconstrained by observations. Low reheating temperature universes with normalcy temperatures of…
The resonant production of keV sterile-neutrino dark matter mainly takes place during the QCD epoch of the early universe. It has been argued that it could be strongly affected by the opacities (or damping rates) of active neutrinos, which…
We propose a simple and flexible mechanism by which sterile neutrinos with masses below the electroweak scale can simultaneously account for the observed baryon asymmetry of the Universe and the dark matter abundance. Crucially, neutrinos…
We consider the possibility of the lightest sterile neutrino dark matter which has dipole interaction with heavier sterile neutrinos. The lifetime can be long enough to be a dark matter candidate without violating other constraints and the…
We generalize gravitational particle production in a radiation-dominated $CPT$-symmetric universe to non-standard, but also $CPT$-symmetric early universe cosmologies. We calculate the mass of a right-handed "sterile" neutrino needed for it…
Secret neutrino interactions can play an essential role in the origin of dark matter. We present an anatomy of production mechanisms for sterile neutrino dark matter, a keV-scale gauge-singlet fermion that mixes with active neutrinos, in…
We consider a class of models in which thermal dark matter is lighter than an MeV. If dark matter thermalizes with the Standard Model below the temperature of neutrino-photon decoupling, equilibration and freeze-out cools and heats the…
We study how the oscillations of the neutrinos affect their thermalization process during the reheating period with temperature O(1) MeV in the early universe. We follow the evolution of the neutrino density matrices and investigate how the…
Sterile neutrinos comprise an entire class of dark matter models that, depending on their production mechanism, can be hot, warm, or cold dark matter. We simulate the Local Group and representative volumes of the Universe in a variety of…
Sterile neutrinos with masses in the keV range can be the dark matter, and their emission from a supernova can explain the observed velocities of pulsars. The sterile neutrino decays could produce the x-ray radiation in the early universe,…
We show that novel paths to dark matter generation and baryogenesis are open when the Standard Model is extended with three sterile neutrinos $N_i$ and a charged scalar $\delta^+$. Specifically, we propose a new production mechanism for the…
Sterile neutrinos produced in the early Universe that mix with active neutrinos of the Standard Model are typically considered to consist of a single population resulting from one dominant production mechanism. We show that the same sterile…
A sterile neutrino with a mass around the keV scale could be an interesting candidate for warm dark matter. Although there are several scenarios and production mechanisms known in which such a particle could yield the correct abundance,…
Sterile neutrinos in the keV mass range have long been considered a well-motivated dark matter (DM) candidate. In this work, we explore a sterile neutrino production mechanism through active neutrino self-interactions in the early universe,…