Large Lepton Mixing and Nonsymmetric Mass Matrices with Flavor 2 <-> 3 Symmetry

We analyze the lepton sector of a recently proposed nonsymmetric mass matrix model. Our model gives a unified description of quark and lepton with the same texture form based on an extended flavor $2 \leftrightarrow 3$ symmetry with a phase. By investigating possible types of assignment for masses, we find that the model can lead to large lepton mixings which are consistent with experimental values. We also find that the model predicts a very small value, $1.3\times10^{-10}$, for the lepton mixing matrix element square $|U_{13}|^2$. The CP violating phases in the lepton mixing matrix and a suppression of the averaged neutrino mass in the neutrinoless double beta decay are also predicted.Comment: 15pages, 2figure

Broken Flavor 2 <-> 3 Symmetry and phenomenological approach for universal quark and lepton mass matrices

A phenomenological approach for the universal mass matrix model with a broken flavor 2 3 symmetry is explored by introducing the 2 3 antisymmetric parts of mass matrices for quarks and charged leptons . We present explicit texture components of the matrices, which are consistent with all the neutrino oscillation experiments and quark mixing data. The mass matrices have a common structure for quarks and leptons, while the large lepton mixings and the small quark mixings are derived with no fine tuning due to the difference of the phase factors. The model predicts a value, 2.4 x 10^{-3}, for the lepton mixing matrix element square |U_{13}|^2, and also predict =(0.89-1.4) x 10^{-4} eV for the averaged neutrino mass which appears in the neutrinoless double beta decay.Comment: 18 page