Speaker
Arghyajit Datta
Description
We present a type-I seesaw scenario within the supersymmetric $U(1)_{B-L}$
extension of the Standard Model that simultaneously explains the large electron–neutrino asymmetry suggested by EMPRESS and the observed tiny baryon asymmetry. Both asymmetries originate from the decay of the $B−L$ Higgs condensate dominating the early Universe. It`s early rare decays into heavy right-handed neutrinos generate baryon asymmetry via resonant leptogenesis, while later decays produce a large lepton asymmetry. The correct magnitudes are obtained for normal neutrino mass hierarchy. The model also predicts a gravitational-wave background from cosmic strings, potentially observable by ultimate DECIGO.