Filtered Baryogenesis

TL;DR

This paper introduces a novel baryogenesis mechanism linked to a filtered dark matter scenario, where a phase transition and CP violation generate both dark matter abundance and baryon asymmetry, compatible with observations.

Contribution

It proposes a new combined mechanism for dark matter and baryon asymmetry generation involving phase transitions and CP violation, with demonstrated parameter dependence and potential to explain observed data.

Findings

Successful baryogenesis demonstrated for multiple portal interactions.

Dark matter abundance can be explained over a wide mass range.

The mechanism links dark matter properties with baryon asymmetry.

Abstract

We propose a new mechanism to simultaneously explain the observed dark matter abundance and the baryon asymmetry of the Universe. The mechanism is based on the Filtered Dark Matter scenario, where dark matter particles acquire a large mass during a first-order phase transition. This implies that only a small fraction of them are energetic enough to enter the advancing true vacuum bubbles and survive until today, while the rest are reflected and annihilate away quickly. We supplement this scenario with a CP-violating interaction, which creates a chiral asymmetry in the population of dark matter particles. In the false vacuum phase, a portal interaction quickly converts the dark sector chiral asymmetry into a Standard Model lepton asymmetry. The lepton asymmetry is then partially converted to a baryon asymmetry by standard electroweak sphaleron processes. We discuss the dependence of the generated asymmetry on the parameters of the model for two different portal interactions and demonstrate successful baryogenesis for both. For one of the portals, it is also possible to simultaneously explain the observed dark matter abundance, over many orders of magnitude in the dark matter mass.