Leptogenesis via Resonant Sequential Dominance and TBC3 Mixing in a Type-I Seesaw Model

Abstract

We demonstrate how phenomenological model construction assuming Sequential Dominance can be extended to cases with degenerate right-handed neutrino masses. Because this framework accommodates resonant leptogenesis, we designate it as Resonant Sequential Dominance. We then investigate Dirac mass matrix textures compatible with current neutrino data within Resonant Sequential Dominance, utilizing a novel neutrino mixing matrix ansatz termed TBC3, proposed in this work. Additionally, we present an $A_4 \times (Z_3)^4 \times (Z_2)^2$-symmetric Lagrangian that is consistent with neutrino oscillation data and successfully drives resonant leptogenesis. Lastly, we find that accounting for the observed baryon asymmetry of the Universe requires the lightest right-handed neutrino mass to lie in the range $0.13\text{ TeV} \le m_{N_1} \le 230\text{ TeV}$.