We present a Dirac leptogenesis model in which the only out-of-equilibrium particles are right-handed neutrinos undergoing asymmetric scatterings. They are produced from a negligible initial abundance and their density freezes in soon after reheating. Even though the asymmetry source term vanishes, we demonstrate that opposite asymmetries of right-handed neutrinos and standard model leptons...
We show that the process of non-instantaneous reheating during the post-inflationary period can have a sizable impact on the charged lepton Yukawa equilibration temperature in the early Universe. This suggests relooking the effects of lepton flavors in the leptogenesis scenario where the production and decay of right-handed neutrinos take place within this prolonged era of reheating. We find...
A derivative coupling of an axion-like particle (ALP) with a B-L current can lead to the baryon asymmetry of the universe through spontaneous leptogenesis, provided there is a lepton number-breaking interaction in thermal equilibrium. Typically, this requires heavy ALPs and a high reheating temperature, as the lepton number-breaking is also linked to neutrino mass generation. In this study, we...
