Abstract:

We show that in supersymmetry models with B-L gauge symmetry, there is a new source for cosmological lepton asymmetry. The Higgs responsible for the B-L symmetry  breaking dominantly decays into right handed neutrinos and their superpartners. Lepton number violation happens in these decays, and is finally converted into baryon number violation by sphaleron interactions. We find the conditions satisfying the observed baryon number asymmetry of the universe and not inducing gravitino abundance problem.