GUT scale inflation, non-thermal leptogenesis, and atmospheric neutrino oscillations

Leptogenesis scenarios in supersymmetric hybrid inflation models are considered. Sufficient lepton asymmetry leading to successful baryogenesis can be obtained if the reheat temperature Tr∼>106 GeV and the superpotential coupling parameter κ is in the range 10-6∼<κ∼<10-2. For this range of κ the scalar spectral index ns≅0.99±0.01. Constraints from neutrino mixing further restrict the range of κ that is allowed. We analyze in detail the case where the inflaton predominantly decays into the next-to-lightest right-handed Majorana neutrino taking into account especially the constraints from atmospheric neutrino oscillations