Baryogenesis via Sterile neutrino oscillation and neutrino parameters

We investigate baryogenesis in the ν MSM which is the Minimal Standard Model (MSM) extended by three right-handed neutrinos with Majorana masses being smaller than the weak scale. In this model three sterile neutrinos, which are almost right-handed states, play important roles in cosmology. The baryon asymmetry of the universe (BAU) is generated via mechanism through flavor oscillation between two sterile neutrinos N 2 and N 3 which are degenerate in masses. We consider the case when BAU is solely originated from the CP violating phases in the mixing matrix of active neutrinos, i.e., the Dirac phase δ and the Majorana phase η , and study how BAU depends on these CP violating phases.