Testing leptogenesis and dark matter production during reheating with primordial gravitational waves

TL;DR

This paper explores how leptogenesis and dark matter production occur during the reheating phase after inflation, analyzing different inflaton potentials and decay modes, and discusses potential detection via primordial gravitational waves.

Contribution

It provides a detailed study of non-thermal leptogenesis and dark matter production during reheating with various inflaton potentials and decay channels, linking these processes to gravitational wave signatures.

Findings

Parameter space for non-thermal leptogenesis is expanded.

Dark matter can be produced via UV freeze-in during reheating.

Primordial gravitational wave spectra can probe reheating scenarios.

Abstract

We study the generation of baryon asymmetry as well as dark matter (DM) in an extended reheating period after the end of slow-roll inflation. Within the regime of perturbative reheating, we consider different monomial potential of the inflaton field during reheating era. The inflaton condensate reheats the Universe by decaying into the Standard Model (SM) bath either via fermionic or bosonic decay modes. Assuming the leptogenesis route to baryogenesis in a canonical seesaw framework, we consider both the radiation bath and perturbative inflaton decay to produce such RHNs during the period of reheating when the maximum temperature of the SM bath is well above the reheating temperature. The DM, assumed to be a SM gauge singlet field, also gets produced from the bath during the reheating period via UV freeze-in. In addition to obtaining different parameter space for such non-thermal leptogenesis and DM for both bosonic and fermionic reheating modes and the type of monomial potential, we discuss the possibility of probing such scenarios via spectral shape of primordial gravitational waves.