Heavy Neutrino as Dark Matter in a Neutrinophilic U(1) Model

TL;DR

This paper explores heavy singlet neutrinos as dark matter candidates within a neutrinophilic U(1) model, detailing how new particles mediate interactions to produce the observed relic density in WIMP and FIMP scenarios.

Contribution

It introduces a neutrinophilic U(1) model with heavy neutrinos as dark matter, analyzing their production mechanisms and parameter space for relic density.

Findings

Heavy neutrinos can serve as dark matter in WIMP and FIMP scenarios.

New gauge boson Z' and scalar portals facilitate relic density production.

Model parameters accommodate observed dark matter abundance.

Abstract

We study the prospect of heavy singlet neutrinos as a dark matter (DM) candidate within a neutrinophilic U(1) model, where the Standard Model (SM) is extended with a U(1) gauge symmetry, and neutrino mass and oscillation parameters are explained through an inverse see-saw mechanism. The lightest of the heavy neutrinos plays the role of the DM while the newly introduced scalars and the extra gauge boson Z' act as mediators between the dark sector and the SM sector. We show the range of model parameters where this DM candidate can be accommodated in the Weakly Interacting Massive Particle (WIMP) or Feebly Interacting Massive Particle (FIMP) scenario. The observed DM relic density is achieved via the new gauge boson and singlet scalar portals in the WIMP scenario whereas within the FIMP scenario, these two particles assume a distinct yet pivotal role in generating the observed relic density of dark matter.