On ${\bf Q}_{6}$ flavor symmetry and the breaking of $\mu \leftrightarrow \tau$ symmetry

Abstract

In the simplest version of a $\mathbf{Q}_{6}$ flavored supersymmetric model, we analyze the leptonic masses and mixings in the framework of a soft breaking of the $\mu \leftrightarrow \tau$ symmetry. This breaking is controlled by the inequality $m_{e\tau}\neq m_{e\mu}$ in the effective neutrino mass. As a consequence of this breaking, the reactor and atmospheric angle are deviate from $0^{\circ}$ and $45^{\circ}$, respectively. Such deviations can be enhanced or suppressed by the CP parities in the Majorana phases, so that an analytic study is carried out to remark their importance to constrain the free parameters that accommodate the mixing angles. The normal hierarchy is completely discarded in this model, the inverted hierarchy is less favored than the degenerate one where the reactor and atmospheric angles are in good agreement with the experimental data. Additionally, the model predicts defined regions for the effective neutrino mass decay, the neutrino mass scale and the sum of the neutrino mass in the inverted and degenerate mass spectrum. Thus, this model may be testable by future experiments that focus in neutrinoless double beta decay.Comment: 21 pages, 20 figures. Improved version, new figures and references added. New section included. Conclusions unchanged. Version accepted for publication in International Journal of Modern Physics