Fermionic dark matter and neutrino masses in a $\mathcal{B-L}$ model

TL;DR

This paper proposes a $ ext{B-L}$ extended standard model that simultaneously addresses neutrino masses via a see-saw mechanism and explores a fermionic dark matter candidate arising from a $Z_2$ symmetry.

Contribution

It introduces a novel $ ext{B-L}$ model with non-standard charges, naturally incorporating a dark matter candidate and explaining neutrino masses within a unified framework.

Findings

The model successfully generates neutrino masses through a low-energy see-saw mechanism.

The fermionic dark matter candidate's relic abundance is consistent with current observations.

The candidate is compatible with existing direct detection constraints.

Abstract

In this work we present a common framework for neutrino mass and dark matter. Specifically, we work with a local $\mathcal{B-L}$ extension of the standard model which has three right-handed neutrinos, $n_{R_{i}}$, and some extra scalars, $\Phi$, $\phi_{i}$ besides the standard model fields. The $n_{R_{i}}$'s have non-standard $\mathcal{B-L}$ quantum numbers and thus these couple to different scalars. This model has the attractive property that an almost automatic $Z_2$ symmetry acting only on a fermionic field, $n_{R3}$, is present. Taking advantage of this $Z_2$ symmetry, we study both the neutrino mass generation via a natural see-saw mechanism in low energy and the possibility of $n_{R3}$ to be a DM candidate. For this last purpose, we study its relic abundance and its compatibility with the current direct detection experiments.