Resonant leptogenesis and TM$_1$ mixing in minimal Type-I seesaw model with S$_4$ symmetry

TL;DR

This paper develops a minimal Type-I seesaw model with S4 symmetry that predicts TM1 neutrino mixing, explores baryogenesis via resonant leptogenesis at TeV scale, and evaluates implications for neutrinoless double beta decay.

Contribution

It introduces a minimal S4 symmetric model with two right-handed neutrinos leading to TM1 mixing and demonstrates baryogenesis through resonant leptogenesis at TeV scale.

Findings

Predicts normal hierarchy for neutrino masses.

Achieves baryon asymmetry of approximately 6.3 x 10^{-10}.

Evaluates effective Majorana neutrino mass relevant for neutrinoless double beta decay.

Abstract

We present an S$_4$ flavour symmetric model within a minimal seesaw framework resulting in mass matrices that leads to TM$_1$ mixing. Minimal seesaw is realized by adding two right-handed neutrinos to the Standard Model. The model predicts Normal Hierarchy (NH) for neutrino masses. Using the constrained six-dimensional parameter space, we have evaluated the effective Majorana neutrino mass, which is the parameter of interest in neutrinoless double beta decay experiments. The possibility of explaining baryogenesis via resonant leptogenesis is also examined within the model. A non-zero, resonantly enhanced CP asymmetry generated from the decay of right-handed neutrinos at the TeV scale is studied, considering flavour effects. The evolution of lepton asymmetry is discussed by solving the set of Boltzmann equations numerically and obtain the value of baryon asymmetry to be $\lvert \eta_B \rvert = 6.3 \times 10^{-10}$.