Gravitino dark matter and Affleck-Dine baryogenesis

Abstract

We study whether gravitino dark matter is compatible with Affleck‐Dine baryogenesis in models with gravity mediated supersymmetry breaking. For a high enough reheating temperature to produce sufficient gravitinos by thermal processes, the observed baryon asymmetry can be explained by Affleck‐Dine baryogenesis as well as thermal leptogenesis. On the other hand, if the reheating temperature is not high enough, most of the gravitinos must be produced by the decay of the next‐to‐lightest supersymmetric particle (NSP). Although such scenarios in general suffer from the late NSP decay which could upset the successful Big Bang Nucleosynthesis, if the NSP problem is avoided and Q‐balls survive the evaporation, Q‐balls can be a source of gravitinos via the NSP decay.