Leptogenesis via multiscalar coherent evolution with supersymmetric neutrino see-saw

Abstract

A novel scenario of leptogenesis is investigated in the supersymmetric neutrino see-saw model. The right-handed sneutrino $ {\tilde N} $ and the $ \phi $ field in the $ {\tilde L} H_u $ direction of the slepton and Higgs doublets start together coherent evolution after the inflation with right-handed neutrino mass $ M_N $ smaller than the Hubble parameter of inflation. Then, after some period the motion of $ {\tilde N} $ and $ \phi $ is drastically changed by the cross coupling $ M_N h_\nu {\tilde N}^* \phi \phi $ from the $ M_N N N $ and $ h_\nu N L H_u $ terms, and the significant asymmetries of $ {\tilde N} $ and $ {\tilde L} $ are generated. The $ {\tilde L} $ asymmetry is fixed later by the thermal effect as the lepton number asymmetry for baryogenesis, while the $ {\tilde N} $ asymmetry disappears through the decays $ {\tilde N} \to {\bar L} {\bar{\tilde H}}_u, {\tilde L} H_u$ with almost the same rate but opposite final lepton numbers.