Thermal keV neutrino dark matter in minimal gauged B-L model with cosmic inflation
Year: 2021
Type: preprint
Abstract: We investigate the possibility of keV scale thermal dark matter in a minimal gauged $B - L$ extension of the standard model with three right-handed neutrinos in the context of cosmic inflation. The complex singlet scalar field responsible for the spontaneous breaking of $B-L$ gauge symmetry is non-minimally coupled to gravity and serves the role of inflaton. The lightest right-handed neutrino $N_1$ can be a dark matter candidate if its couplings to leptons are sufficiently suppressed or forbidden. While keV scale $N_1$ gives rise to the possibility of warm dark matter, its thermal production leads to over-abundance. The subsequent entropy dilution due to heavier right-handed neutrino decay can bring the DM abundance within the observed limit. We constrain the model parameters from the requirement of producing sufficient entropy dilution, inflationary observables along with other phenomenological constraints. While these requirements cannot satisfy light neutrino data, suitable extension of the minimal model can accommodate it.
Source: arXiv (Cornell University)
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3209103997