CP violating decays in leptogenesis scenarios

Abstract We compute the CP violation in the decays of heavy electroweak singlet neutrinos, arising from both the one-loop vertex corrections and the wave function mixing. We extend the computation to the supersymmetric version of the model and discuss the implications for the generation of a lepton number asymmetry by the out of equilibrium decay of the heavy (s) neutrinos in the early Universe, to be reprocessed later in the observed baryon excess by anomalous electroweak processes.