Neutrino mass and asymmetric dark matter: study with inert Higgs doublet and high scale validity

TL;DR

This paper explores an inert Higgs doublet extension of the Standard Model that simultaneously addresses dark matter, neutrino mass, and baryon asymmetry, while analyzing the model's high scale validity and parameter constraints.

Contribution

It introduces a unified framework combining inert Higgs doublet, right-handed neutrinos, and a dark sector, and studies its viability considering multiple cosmological and particle physics constraints.

Findings

Existence of a small, non-zero DM relic density contribution from IHD.

High scale validity significantly constrains the model's parameter space.

The model successfully explains dark matter, neutrino masses, and baryon asymmetry within the constrained parameters.

Abstract

We consider an inert Higgs doublet (IHD) extension of the Standard Model accompanied with three right handed neutrinos and a dark sector, consisting of a singlet fermion and a scalar, in order to provide a common framework for dark matter, leptognesis and neutrino mass. While the Yukawa coupling of the right handed neutrinos with IHD (having mass in the intermediate regime: 80-500 GeV) is responsible for explaining the observed baryon asymmetry through leptogenesis, its coupling with the dark sector explains the dark matter relic density. The presence of IHD also explains the neutrino mass through radiative correction. We find that study of the high scale validity of the model in this context becomes crucial as it restricts the parameter space significantly. It turns out that there exists a small, but non-zero contribution to the relic density of DM from IHD too. Considering all the constraints from dark matter, leptogenesis, neutrino mass and high scale validity of the model, we perform a study to find out the viable parameter space.