Leptogenesis as a Common Origin for Matter and Dark Matter

TL;DR

This paper presents a model linking matter and dark matter origins through leptogenesis, proposing a mirror universe with identical forces and matter, where asymmetries generated in the early universe explain observed densities.

Contribution

It introduces a symmetric mirror universe model with leptogenesis-driven asymmetries, connecting dark matter and baryonic matter origins via heavy neutrino decays.

Findings

Dark matter density is higher due to heavier dark nucleons.

Leptogenesis generates equal lepton asymmetry in both sectors.

Neutrino masses arise from inverse seesaw mechanism.

Abstract

We propose a model of asymmetric dark matter (DM) where the dark sector is an identical copy of both forces and matter of the standard model (SM) as in the mirror universe models discussed in literature. In addition to being connected by gravity, the SM and DM sectors are also connected at high temperature by a common set of heavy right-handed Majorana neutrinos via their Yukawa couplings to leptons and Higgs bosons. The lightest nucleon in the dark (mirror) sector is a candidate for dark matter. The out of equilibrium decay of right-handed neutrino produces equal lepton asymmetry in both sectors via resonant leptogenesis which then get converted to baryonic and dark baryonic matter. The dark baryon asymmetry due to higher dark nucleon masses leads to higher dark matter density compared to the familiar baryon density that is observed. The standard model neutrinos in this case acquire masses from the inverse seesaw mechanism. A kinetic mixing between the U(1) gauge fields of the two sectors is introduced to guarantee the success of Big-Bang Nucleosynthesis.