Neutrino masses, mixing and leptogenesis in type-I seesaw with A4 symmetry

Abstract

In order to explain the observed nonzero value of themixing angle θ13, we have analyzed the neutrino mass matrix generated by a A4 flavor symmetric type-I seesaw. The vacuum expectation value (vev) of a flavon induces the nonzero θ13 by breaking the exact tribimaximal (TBM) pattern. The Majorana phases involved in the lepton mixing matrix are modified in presence of this vev as compared to the TBM case. So, a lepton asymmetry in this model is viable, once the next-to-leading order contribution to the neutrino Yukawa coupling is considered.