Neutrino spectrum in SU$(3)_\ell\times$SU$(3)_E$ gauged lepton flavor model

Abstract

Massive neutrino is an evidence of new physics beyond the Standard Model. One of the well motivated new physics scenarios is a model with gauged lepton flavor symmetry. We investigate neutrino properties in the minimal SU$(3)_\ell\times$SU$(3)_E$ gauged lepton flavor model. In this model, three new species of fermions are introduced to cancel gauge anomalies. These new fermions lead to a see-saw mechanism for neutrino mass generation. We impose the constraints from perturbative unitarity in 2-2 scattering processes, as well as current experimental constraints, to obtain viable neutrino spectrum. We determine the lower bound, with the SU(3)$_\ell$ gauge coupling set to 1, on the lightest neutrino mass of $3.76\times10^{-3}\,(18.9\times10^{-3})\,$ eV for the normal (inverted) hierarchy.