Flavor S4 ⊗ Z2 symmetry and neutrino mixing

We present a model of the lepton masses and flavor mixing based on the discrete group S-4 circle times Z(2). In this model, all the charged leptons and neutrinos are assigned to the 3 alpha representation of S-4 in the Yamanouchi bases. The charged lepton and neutrino masses are mainly determined by the vacuum expectation value structures of the Higgs fields. A nearly tri-bimaximal lepton flavor mixing pattern, which is in agreement with the current experimental results, can be accommodated in our model. The neutrino mass spectrum takes the nearly degenerate pattern, and thus can be well tested in the future precise experiments. (C) 2007 Elsevier B.V. All rights reserved.