Non-Zero ${\theta }_{13}$ and ${\delta }_{CP}$ in a Neutrino Mass Model with $A_4$ Symmetry

Abstract

In this paper, we consider a neutrino mass model based on $A_4$ symmetry. The spontaneous symmetry breaking in this model is chosen to obtain tribimaximal mixing in the neutrino sector. We introduce $Z_2\times Z_2$ invariant perturbations in this model which can give rise to acceptable values of ${\theta }_{13}$ and ${\delta }_{CP}$. Perturbation in the charged lepton sector alone can lead to viable values of ${\theta }_{13}$, but cannot generate ${\delta }_{CP}$. Perturbation in the neutrino sector alone can lead to acceptable ${\theta }_{13}$ and maximal CP violation. By adjusting the magnitudes of perturbations in both sectors, it is possible to obtain any value of ${\delta }_{CP}$.

Comments: 16 pages, 3 figures