S4 x Z2 Flavor Symmetry in Supersymmetric Extra U(1) Model
Abstract
We propose a E6 inspired supersymmetric model with a non-Abelian discrete flavor symmetry (S4 group); that is, SU(3)c x SU(2)W x U(1)Y x U(1)X x S4 x Z2. In our scenario, the additional abelian gauge symmetry; U(1)X, not only solves the mu-problem in the minimal Supersymmetric Standard Model(MSSM), but also requires new exotic fields which play an important role in solving flavor puzzles. If our exotic quarks can be embedded into a S4 triplet, which corresponds to the number of the generation, one finds that dangerous proton decay can be well-suppressed. Hence, it might be expected that the generation structure for lepton and quark in the SM(Standard Model) can be understood as a new system in order to stabilize the proton in a supersymemtric standard model (SUSY). Moreover, due to the nature of the discrete non-Abelian symmetry itself, Yukawa coupling constants of our model are drastically reduced. In our paper, we show two predictive examples of the models for quark sector and lepton sector, respectively.