Majorana Neutrino Masses from Anomalous U(1) Symmetries

Abstract

We explore the possibility of interpreting the solar and atmospheric neutrino data within the context of the Minimal Supersymmetric Standard Model augmented by a single U(1) anomalous family symmetry spontaneously broken by non-zero vacuum expectation values of a pair of singlet fields. The symmetry retains a dimension-five operator which provides Majorana masses for left-handed neutrino states. Assuming symmetric lepton mass matrices, the model predicts inverse hierarchical neutrino mass spectrum, theta_{13}=0 and large mixing while at the same time it provides acceptable mass matrices for the charged fermions.