Flavoured resonant leptogenesis at sub-TeV scales

Abstract

We consider sub-TeV scale flavoured resonant leptogenesis within the minimal type-I seesaw scenario with two right-handed singlet neutrinos N1,2 forming a pseudo-Dirac pair, concentrating on the case of masses of the pseudo-Dirac pair having values M1,2≲100 GeV. The case when the CP violating asymmetries in the individual lepton charges Ll, l=e,μ,τ, and in the total lepton charge L of the Universe are generated in 1↔2 decay processes is investigated. We show that successful leptogenesis is possible for M1,2 lying in the interval M1,2=(0.3−100) GeV. Our results show also, in particular, that for vanishing initial N1,2 abundance, flavour effects can play an important role in the generation of the baryon asymmetry, leading to an enhancement of the asymmetry by a factor up to ∼300 with respect to the “unflavoured” leptogenesis scenario.