Non-zero $\theta_{13}$, CP-violation and Neutrinoless Double Beta Decay for Neutrino Mixing in the $A_4\times Z_2\times Z_3$ Flavor Symmetry Model

TL;DR

This paper extends an $A_4$ flavor symmetry model with additional flavons and symmetries to generate realistic neutrino mixing parameters, including a non-zero $ heta_{13}$, and explores implications for neutrinoless double beta decay.

Contribution

It introduces higher order corrections via new flavons and symmetries to produce realistic neutrino mixing angles and mass hierarchies consistent with experimental data.

Findings

Non-zero $ heta_{13}$ achieved through perturbations.

Neutrino mass hierarchies analyzed with respect to model parameters.

Predictions for neutrinoless double beta decay parameter $m_{etaeta}$.

Abstract

We study the modification of the Altarelli-Feruglio $A_4$ flavor symmetry model by adding three singlet flavons $\xi'$, $\xi''$ and $\rho$ and the model is augmented with extra $Z_2\times Z_2^ \prime$ symmetry to prevent the unwanted terms in our study. The addition of these three flavons lead to two higher order corrections in the form of two perturbation parameters $\epsilon$ and $\epsilon^\prime$. These corrections yield the deviation from exact tri-bimaximal (TBM) neutrino mixing pattern by producing a non-zero $\theta_{13}$ and other neutrino oscillation parameters which are consistent with the latest experimental data. In both the corrections, the neutrino masses are generated via Weinberg operator. The analysis of the perturbation parameters $\epsilon$ and $\epsilon^\prime$, shows that normal hierarchy (NH) and inverted hierarchy (IH) for $\epsilon$ does not change much. However, as the values of $\epsilon^\prime$ increases, $\theta_{23}$ occupies the lower octant for NH case. We further investigate the neutrinoless double beta decay parmeter $m_{\beta\beta}$ using the parameter space of the model for both normal and inverted hierarchies of neutrino masses.