Minimal seesaw model with S_4 flavor symmetry

TL;DR

This paper presents a minimal neutrino mass model using S_4 flavor symmetry within the seesaw framework, successfully explaining observed neutrino mixing patterns with fewer parameters.

Contribution

It introduces a minimal seesaw model with S_4 symmetry, reducing free parameters while naturally reproducing neutrino mixing and mass hierarchy.

Findings

Achieves nearly tri-bimaximal mixing pattern

Heavy right-handed neutrinos are non-degenerate

Normal hierarchy is compatible with experimental data

Abstract

We discuss a neutrino mass model based on the S_4 flavor symmetry within the minimal seesaw framework, in which only two right-handed neutrinos are introduced and transform as 2 under S_4. Although the model contains less free parameters compared to the typical seesaw models, it provides a successful description of the observed neutrino parameters, and in particular, a nearly tri-bimaximal mixing pattern can be naturally accommodated. In addition, the heavy right-handed neutrino masses are found to be non-degenerate, while only the normal hierarchical mass spectrum is compatible with experiments for light neutrinos.