Deviation from tri-bimaximal mixing and flavor symmetry breaking in a seesaw type A4 model

TL;DR

This paper investigates how higher order corrections in an A4 flavor symmetry model with supersymmetry cause deviations from tri-bimaximal neutrino mixing, predicting specific bounds on mixing angles and analyzing lepton flavor violation.

Contribution

It introduces a detailed analysis of higher order effects in an A4 seesaw model with SUSY, providing predictions for neutrino mixing deviations and lepton flavor violation constraints.

Findings

$ heta_{23}$ mixing angle is larger than 0.96

Upper bound of $ heta_{13}$ is 0.01

Lepton flavor violation is suppressed within experimental limits

Abstract

We have studied the contribution of higher order corrections of the flavor symmetry breaking in the $A_4$ seesaw model with the supersymmetry. Taking account of possible higher dimensional mass operators, we predict the deviation from the tri-bimaximal lepton mixing for both normal hierarchy and inverted hierarchy of neutrino masses. We have found that the value of $\sin^2 2\theta_{23}$ is larger than 0.96 and the upper bound of $\sin^2\theta_{13}$ is 0.01. We have also examined the flavor changing neutral current of leptons from the soft SUSY breaking in slepton masses and A-terms within the framework of supergravity theory. Those magnitudes are enough suppressed to be consistent with experimental constraints.