Neutrino mass and mixing, resonant leptogenesis and charged lepton flavor violation in a minimal seesaw model with $S_4$ symmetry

Abstract

We propose a minimal inverse seesaw model with $S_4$ symmetry for the Majorana neutrinos with only one real ($m_0$)-and two complex ($α, β$) parameters in neutrino sector which gives reasonable predictions for the neutrino oscillation parameters, the observed baryon asymmetry of the Universe and the charged lepton flavor violation. The resulting model reveals a favor for normal neutrino mass ordering, a higher octant of $θ_{23}$ and a lower half-plane of Dirac CP violation phase. The predictions of the model for sum of neutrino masses and the effective Majorana neutrino mass are centered around 58.98 meV and 6.2 meV, respectively. The model also provides the predictions of the baryon asymmetry and charged lepton flavour violation processes which are consistent with the experimental observations.

Figures (7)

• Figure 1: Pairwise relationships between the neutrino model parameters. The values of likelihood and weight are shaded in different colours. These colours indicate the combination of weight (volume in parameter space) and likelihood (quality of fit). High-weight points represent broad allowed regions, while high likelihood points corresponds to better fits to the experimental data. The orange colour indicate the free parameter values which fit the neutrino oscillation data with high accuracy.
• Figure 2: Allowed regions of (a) Re[$\alpha$] and Im$[\alpha]$, and (b) of Re[$\beta$] and Im$[\beta]$.
• Figure 3: Predicted values of neutrino mixing angles ($\sin^2\theta_{23},\sin^2\theta_{12}$, $\sin^2\theta_{13}$), mass squared differences $(\Delta m_{21}^2, \Delta m_{31}^2)$ and $m_o$.
• Figure 4: Predicted values of Dirac CP-violating phase $\delta_{CP}$ and effective mass parameter $m_{\beta\beta}$.
• Figure 5: Variation of $\eta_B$ with the model parameters.