A Left-Right Symmetric Model for Neutrino Masses, Baryon Asymmetry and Dark Matter

TL;DR

This paper proposes a left-right symmetric model where heavy singlet fermion decays generate neutrino masses, baryon asymmetry, and dark matter, linking these phenomena through the model's symmetry.

Contribution

It introduces a novel left-right symmetric framework without bi-doublet Higgs scalars, connecting neutrino mass generation, baryon asymmetry, and dark matter properties.

Findings

Heavy neutral singlet fermion decays produce neutrino masses and asymmetries.

Dark matter relic density is related to neutrino mass generation.

Decays of right-handed neutrinos explain Galactic 511 keV photon fluxes.

Abstract

In the left-right symmetric models without bi-doublet Higgs scalars, the standard model fermions can obtain masses by integrating out heavy charged singlet fermions. We find the decays of heavy neutral singlet fermions, responsible for generating small neutrino masses, can simultaneously produce a left-handed lepton asymmetry for baryon asymmetry and a relic density of right-handed neutrinos for dark matter. Benefited from the left-right symmetry, the properties of the dark matter can be related to the generation of the neutrino masses and the baryon asymmetry. We also indicate that the decays of the non-thermally produced right-handed neutrinos can explain the observed fluxes of 511 keV photons from the Galactic bulge.