Baryogenesis and Dark Matter from non-thermally produced WIMPs

TL;DR

This paper explores a simplified model where a non-thermally produced WIMP-like particle decay during early matter domination generates both baryon asymmetry and dark matter, highlighting the importance of non-standard cosmological evolution.

Contribution

It demonstrates that non-standard early Universe scenarios can produce sufficient baryon asymmetry and dark matter from WIMP decay within collider-accessible mass ranges.

Findings

Standard cosmology cannot produce enough baryon asymmetry with TeV-scale BSM particles.

A matter-dominated phase prior to radiation domination resolves this issue.

Dark matter can be non-thermally generated during early matter domination.

Abstract

We illustrate, via a simplified model, a scenario in which the baryon-asymmetry and, possibly the dark matter component of the Universe are simultaneously generated by the decay of a WIMP-like mother particle, in turn produced non-thermally during an epoch of Early Matter domination. We first consider the standard evolution of the Universe and introduce TeV-scale BSM particles, finding that this paradigm cannot produce enough baryon asymmetry. This deficiency can be resolved by considering a non-standard scenario, with a matter-dominated phase prior to radiation-domination. Finally, we include a dark matter candidate, which is non-thermally produced during the Early Matter domination. Our results demonstrate an interesting common origin of baryon asymmetry and Dark Matter, with the particle masses lying within the collider-detectable range, thanks to the presence of non-standard evolution in the early Universe.