Successful type I leptogenesis with SO(10)-inspired mass relations

摘要

It is well known that thermal leptogenesis through the decays of the lightest right-handed neutrinosencounters serious difficulties when SO(10)-inspired mass conditions are imposed on the Dirac neutrinomass matrix and light neutrino masses are generated through the type I see-saw mechanism. We showthat these can be circumvented when the production from the next-to-lightest right-handed neutrinosand flavor effects are properly taken into account. Some conditions on the low energy parameters haveto be satisfied in order to explain the observed matter-antimatter asymmetry. In particular we find m1 >10-3 eV, where m1 is the mass of the lightest left-handed neutrino and that non-vanishing values of themixing angle 913 are preferred in the case of a normal fully hierarchical spectrum of light neutrinos.