Nonzero U_{e3}, CP violation and leptogenesis in a see-saw type softly broken A_4 symmetric model

TL;DR

This paper presents a model where non-zero U_{e3} and CP violation naturally emerge, linking low-energy neutrino phenomena with leptogenesis, and demonstrating compatibility with observed baryon asymmetry.

Contribution

It introduces a softly broken A_4 symmetric see-saw model that generates non-zero U_{e3} and CP violation, connecting low-energy neutrino data with leptogenesis.

Findings

Non-zero U_{e3} generated through a single parameter perturbation.

Large low-energy CP violation (J_{CP} ≈ 10^{-2}) observed.

Leptogenesis produces baryon asymmetry consistent with WMAP data.

Abstract

We have shown that non-zero U_{e3} is generated in a see-saw type softly broken A_4 symmetric model through a single parameter perturbation in m_D in a single element. We have explored all possible 9 cases to study the neutrino mixing angles considering the best fitted values of \Delta m_{\odot}^2 and \Delta m_{atm}^2 with all parameters real. We have extended our analysis for the complex case and demonstrated large low energy CP violation (J_{CP}\simeq 10^{-2}) and m_{ee} in addition to mixing and mass pattern. We have also investigated leptogenesis and for a reasonable choice of model parameters compatible with low energy data, WMAP value of baryon asymmetry 6\times 10^{-10} is obtained for right handed neutrino mass scale M_0\simeq 10^{13} GeV. We have obtained a relation among the phases responsible for leptogenesis and have shown that these phases also have correlations with low energy CP violating phases.