Predictive Model of Inverted Neutrino Mass Hierarchy and Resonant Leptogenesis

Abstract

We present a new realization of inverted neutrino mass hierarchy based on $S_3\times \mathcal{U}(1)$ flavor symmetry. In this scenario, the deviation of the solar oscillation angle from $\pi /4$ is correlated with the value of ${\theta }_{13}$, as they are both induced by a common mixing angle in the charged lepton sector. We find several interesting predictions: ${\text{te}}_{13}\ge 0.13$, ${\sin }^2{\text{te}}_{12}\ge 0.31$, ${\sin }^2{\text{te}}_{23}\simeq 0.5$ and $0\le \cos \text{de}\le 0.7$ for the neutrino oscillation parameters and $0.01\mathrm{eV}\stackrel{<}{{}_{\sim }}{m}_{\text{bt}\text{bt}}\stackrel{<}{{}_{\sim }}0.02\mathrm{eV}$ for the effective neutrino mass in neutrino-less double $\text{bt}$-decay. We show that our scenario can also explain naturally the observed baryon asymmetry of the universe via resonant leptogenesis. The masses of the decaying right--handed neutrinos can be in the range $(10^3-10^7)$ GeV, which would avoid the generic gravitino problem of supersymmetric models.

Comments: Model slightly improved, references added, version will appear in IJMP