Late Time Entropy Production in Leptogenesis Scenarios

Abstract

In this thesis we will consider Standard Model (SM) Leptogenesis scenarios and determine the maximally allowed entropy production with respect to the mass of the lightest right handed neutrino. We extend the SM Leptogenesis model as a Minimal Supersymmetric Standard Model (MSSM) to determine the viability of the Stau as the next to lightest supersymmetric particle (NLSP). We consider the viability of the Stau NLSP by taking into account the entropy dilution factor found in the MSSM Leptogenesis scenario and considering Big Bang Nucleosynthesis constraints.