Matter-antimatter asymmetry and neutrino properties

The cosmological baryon asymmetry can be explained as remnant of heavy Majorana neutrino decays in the early universe. We study this mechanism for two models of neutrino masses with a large nu(mu) - nu(tau) mixing angle which are based on the symmetries SU(5) x U(1)(F) and SU(3)(c) x SU(3)(L) x SU(3)(R) x U(1)(F), respectively. In both cases B - L is broken at the unification scale Lambda(GUT) The models make different predictions for the baryogenesis temperature and the gravitino abundance. (C) 1999 Elsevier Science B.V. All rights reserved.