Dark Photon Dark Matter in the minimal $B-L$ Model

TL;DR

This paper investigates whether the gauge boson associated with the $U(1)_{B-L}$ symmetry in the minimal $B-L$ model can serve as a viable dark matter candidate, linking neutrino mass generation, leptogenesis, and dark matter.

Contribution

It explores the potential of the $U(1)_{B-L}$ gauge boson as a dark matter candidate within the minimal $B-L$ model, connecting neutrino physics and cosmology.

Findings

The $U(1)_{B-L}$ gauge boson can be a viable dark matter candidate under certain conditions.

The model links neutrino mass generation, leptogenesis, and dark matter in a unified framework.

Conditions for the gauge boson to account for the observed dark matter abundance are identified.

Abstract

The extension of the Standard model (SM) with three heavy right handed neutrinos, a complex scalar and the gauged $U(1)_{\rm B-L}$ symmetry (the minimal $B-L$ model) is considered the most compelling minimal one: the presence and the out-of-equilibrium decay of the heavy right handed neutrinos can account for the small masses of the active neutrinos and the baryon asymmetry of the universe. A natural accompanying question concerns whether the minimal $B-L$ model can naturally accommodate an interesting dark matter (DM) candidate. We study the possibility where the current DM population is explained by the gauge boson of $U(1)_{\rm B-L}$ symmetry. We discuss how the minimal set-up originally aimed at the seesaw mechanism and the leptogenesis is connected to conditions making the gauge boson promoted to a DM candidate.