Similar Dark Matter and Baryon abundances with TeV-scale Leptogenesis

TL;DR

This paper investigates how TeV-scale leptogenesis in an inverse seesaw model can naturally produce similar dark matter and baryon abundances, linking CP violation, baryon asymmetry, and WIMP relic density.

Contribution

It proposes a mechanism connecting baryon asymmetry and dark matter densities through TeV-scale leptogenesis with specific CP violation conditions.

Findings

Baryon asymmetry depends on CP asymmetry epsilon and mass ratio M/m_W.

The baryon/WIMP ratio is approximately epsilon times M/m_W.

A natural explanation for similar densities is CP violation of order m_W/M.

Abstract

We estimate the Baryon Asymmetry of the Universe (BAU) produced in an inverse seesaw model containing extra light singlets, and with lepton number conservation prior to the electroweak phase transition. An order one CP asymmetry epsilon is required to obtain a large enough BAU. We discuss the relation between the baryon and WIMP relic densities in baryogenesis scenarios using the out-of-equilibrium decay of a baryon-parent of mass M: when baryon number violation freezes out, the remaining density of baryon-parents is of order M/m_W times the WIMP relic density. So the baryon/WIMP ratio is or order epsilon M/m_W. A natural explanation of the similar WIMP and baryon densities could be that CP violation is of order the ratio m_W/M.