Neutrino masses and $\mu$ terms in a supersymmetric extra U(1) model

Abstract

We propose a supersymmetric extra U(1) model, which can generate small neutrino masses and necessary $\mu$ terms, simultaneously. Fields including quarks and leptons are embedded in three ${\bf 27}$s of $E_6$ in a different way among generations. The model has an extra U(1) gauge symmetry at TeV regions, which has discriminating features from other models studied previously. Since a neutrino mass matrix induced in the model has a constrained texture with limited parameters, it can give a prediction. If we impose neutrino oscillation data to fix those parameters, a value of $\sin\theta_{13}$ can be determined. We also discuss several phenomenological features which are discriminated from the ones of the MSSM.