Leptogenesis in a Δ(27) × SO(10) SUSY GUT

Abstract

Although SO(10) Supersymmetric (SUSY) Grand Unification Theories (GUTs) are very attractive for neutrino mass and mixing, it is often quite difficult to achieve successful leptogenesis from the lightest right-handed neutrino N1due to the strong relations between neutrino and up-type quark Yukawa couplings. We show that in a realistic model these constraints are relaxed, making N1leptogenesis viable. To illustrate this, we calculate the baryon asymmetry of the Universe YBfrom flavoured N1leptogenesis in a recently proposed Δ(27) × SO(10) SUSY GUT. The flavoured Boltzmann equations are solved numerically, and comparison with the observed YBplaces constraints on the allowed values of right-handed neutrino masses and neutrino Yukawa couplings. The flavoured SO(10) SUSY GUT is not only fairly complete and predictive in the lepton sector, but can also explain the BAU through leptogenesis with natural values in the lepton sector albeit with some tuning in the quark sector.