Minimal 3-3-1 model with a spectator sextet

TL;DR

This paper explores a minimal 3-3-1 model incorporating a heavy scalar sextet, proposing mechanisms for charged lepton and neutrino mass generation, and analyzing scalar spectra and potential stability.

Contribution

It introduces a minimal 3-3-1 model with a scalar sextet that explains lepton masses via combined seesaw mechanisms and details conditions for potential stability.

Findings

Charged lepton masses from a type-II seesaw-like mechanism.

Neutrino masses generated by a type-I mechanism.

Scalar potential stability conditions identified.

Abstract

We consider the minimal 3-3-1 model with a heavy scalar sextet and realize, at the tree level, an effective dimension-five interaction that contributes to the mass of the charged leptons. In this case the charged leptons masses arise from a sort of type-II seesawlike mechanism while the neutrino masses are generated by a type-I mechanism. We also show that the parameters giving the correct lepton masses also accommodate the Pontecorvo-Maki-Nakawaga-Sakata matrix. We give the scalar mass spectra of the model and analyze under which conditions the fields in the scalar sextet are heavy even with small or zero vacuum expectation values. We also show the conditions under which it is possible to have a stable (bounded from below) potential and also a global minimum.