Nonzero of mixing angle $\theta_{ 13}$ has some phenomenological consequences on neutrino physics beyond the standard model. If the mixing angle $\theta_{ 13}\neq 0$, then there is the possibility of the CP violation existence on the neutrino sector. To obtain a nonzero of mixing angle $\theta_{ 13}$ from neutrino mass matrix obey $\mu-\tau$, we break it by introducing one small parameter $x$ into neutrino mass matrix and then calculated the Jarlskog invariant as a measure of CP violation existence using the reported experimental data as input and put $m_{ 1}=0$ for neutrino mass in normal hierarchy.
Categories: hep-ph