An $A_4$ realization of inverse seesaw: neutrino masses, $\theta_{13}$ and leptonic non-unitarity

TL;DR

This paper presents an $A_4$ flavor symmetric model implementing the inverse seesaw mechanism to explain light neutrino masses and mixing, including nonzero $ heta_{13}$ and leptonic non-unitarity effects.

Contribution

It introduces a novel $A_4$ flavor symmetry framework that links neutrino mixing angles, CP violation, and non-unitarity effects within the inverse seesaw model.

Findings

Correlation between $ heta_{13}$ and other parameters elucidated.

Non-unitarity effects impact lepton flavor violating decays.

Model reproduces observed neutrino mixing patterns.

Abstract

We provide an $A_4$ based flavor symmetric scenario to accommodate the inverse seesaw mechanism for explaining light neutrino masses and mixing. We find that the lepton mixing, in particular the tri-bimaximal mixing pattern and its deviation through nonzero $\theta_{13}$, is originated solely from the flavor structure of the lepton number violating contribution of the neutral lepton mass matrix. Here we discuss in detail how a nonzero value of $\theta_{13}$ is correlated with the other parameters in the framework and its impact on the Dirac CP phase $\delta$. We also analyze the non-unitarity effects on lepton mixing matrix and its implication in terms of the lepton flavor violating decays, etc..