Fermion and scalar phenomenology of a 2-Higgs doublet model with $S_3$

TL;DR

This paper introduces a 2-Higgs doublet model extended by specific discrete symmetries, explaining fermion masses, mixing, and neutrino properties, with detailed analysis of scalar sector phenomenology and experimental constraints.

Contribution

It presents a novel 2-Higgs doublet model with extended symmetries that naturally explains fermion mass hierarchies and lepton mixing angles, including neutrino masses via a type I seesaw.

Findings

Model predicts fermion mass hierarchies and mixing angles consistent with observations.

Scalar sector analysis constrains model parameters through decay channels and electroweak precision tests.

Lepton mixing angles are nearly tri-bi-maximal, matching experimental data.

Abstract

We propose a 2-Higgs doublet model where the symmetry is extended by $S_{3}\otimes Z_{3}\otimes Z_{3}^{\prime }\otimes Z_{14}$ and the field content is enlarged by extra $SU(2)_{L}$ singlet scalar fields. $S_3$ makes the model predictive and leads to viable fermion masses and mixing. The observed hierarchy of the quark masses arises from the $Z_{3}^{\prime }$ and $Z_{14}$ symmetries. The light neutrino masses are generated through a type I seesaw mechanism with two heavy Majorana neutrinos. In the lepton sector we obtain mixing angles that are nearly tri-bi-maximal, in an excellent agreement with the observed lepton parameters. The vacuum expectation values required for the model are naturally obtained from the scalar potential, and we analyze the scalar sector properties further constraining the model through the $\gamma \gamma$ decay channel and the $T$ and $S$ parameters.