Lepton masses and mixing in $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ models with a $S_3$ flavor symmetry

TL;DR

This paper introduces a model using $SU(3)_C imes SU(3)_L imes U(1)_X$ gauge symmetry combined with $S_3$ flavor symmetry to explain lepton masses and mixing, including neutrino mass hierarchy and CP violation.

Contribution

It presents a novel $SU(3)_C imes SU(3)_L imes U(1)_X$ model with $S_3$ symmetry that naturally generates neutrino masses and mixing consistent with experimental data.

Findings

Neutrino spectrum is quasi-degenerate with normal hierarchy.

Model predicts $ heta_{13}$ and CP violation consistent with experiments.

Neutrino masses arise via a double seesaw mechanism.

Abstract

We propose a model based on the gauge group $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ with an extra $S_{3}$ flavor symmetry, which accounts for the lepton masses and mixing. The small active neutrino masses are generated via a double seesaw mechanism. In this scenario, the spectrum of neutrinos presents very light, light and very heavy masses. The model predicts a quasidegenerate normal hierarchy active neutrino mass spectrum and the relation $\Delta m_{21}^{2}\ll \Delta m_{31}^{2}$ arises from effective six-dimensional operators. The obtained neutrino mixing parameters are in agreement with the neutrino oscillation experimental data. We find CP violation in neutrino oscillations with a Jarlskog invariant of about $10^{-2}$.