Two-component Dark Matter and low scale Thermal Leptogenesis

TL;DR

This paper proposes a two-component dark matter model integrated with low-scale thermal leptogenesis, linking baryon asymmetry, neutrino masses, and dark matter, and explores its testable parameter space.

Contribution

It introduces a novel two-component dark matter scenario within an extended Scotogenic model that connects baryogenesis, neutrino masses, and dark matter phenomenology.

Findings

Identifies parameter space consistent with baryon asymmetry, neutrino masses, and dark matter constraints.

Establishes correlations between dark matter particles and leptogenesis.

Highlights potential for future detection experiments to test the model.

Abstract

The observable cosmos exhibits sizable baryon asymmetry, small active neutrino masses, and the presence of dark matter (DM). To address these phenomena together, we propose a two component DM scenario in an extension of Scotogenic model, imposing $\mathbb{Z}_2 \otimes \mathbb{Z}_2^{\prime}$ symmetry. The electroweak sphaleron process converts the $\rm Y_{B-L}^{}$ yield, generated through the Leptogenesis mechanism, into the baryon asymmetry ($\rm Y_{\Delta B}^{}$) at $\rm T_{\rm sph}\sim 130$ GeV, the sphalerons decoupling temperature. In this framework, the CP asymmetry as well as the radiative neutrino mass generation explicitly involve the two DM particles, thus establishing a correlation between the baryon asymmetry, DM and observed active neutrino masses. We study in details the allowed parameter space available after considering all the constraints from the three phenomena as well as from the collider search limits, and outline the region which could potentially be tested in future DM detection experiments through direct or indirect detection searches, lepton flavor-violating decays, etc.