Speaker
Description
We introduce a neutrino mass model for leptogenesis where three right-handed Majorana neutrinos are involved and the minimal-extended seesaw mechanism produces four(3+1) light neutrinos. The CP asymmetry produced from the decays of heavy neutrinos and the dilution mass are described only in terms of the mixing elements of the fourth neutrino, $U_{e4}, U_{\mu 4}$ and $U_\tau 4$ which current oscillation experiments challenge to probe. As a result, the existence of an additional light neutrino is required to explain the high-energy lepton asymmetry in terms of low-energy phenomenology, and the energy scale of leptogenesis $M_1$ is also predicted by the mass of the sterile neutrino. In low energy, both sterile neutrino oscillation experiments and neutrinoless double-beta decay experiments can narrow down the parameter ranges so that the model can be tested. Especially, the bounds of $U_{\alpha 4}$ constrained by the observed baryon asymmetry are provided. This presentation includes both normal-ordering and inverted-ordering cases.
