Five-zero texture in neutrino-dark matter model within the framework of minimal extended seesaw

TL;DR

This paper presents a minimal extended seesaw model with five-zero textures, incorporating flavor symmetries to explain neutrino masses, dark matter, and baryogenesis, and explores related phenomenological implications.

Contribution

It introduces a novel five-zero texture in the active-sterile neutrino mass matrix within a minimal extended seesaw framework, linking neutrino physics, dark matter, and baryogenesis.

Findings

Bound active-sterile mixing parameters using neutrino oscillation data.

Achieved resonant leptogenesis at TeV scale with flavor effects.

Identified a scalar dark matter candidate consistent with relic density.

Abstract

We study a model of neutrino and dark matter within the framework of a minimal extended seesaw. This model is based on $A_4$ flavour symmetry along with the discrete $Z_3\times Z_4$ symmetry to stabilize the dark matter and construct desired mass matrices for neutrino mass. Five-zero textures are imposed in the final $4\times4$ active-sterile mass matrix, which significantly reduces free parameter in the model. Three right-handed neutrinos were considered, two of them have nearly degenerate masses which help us to achieve baryogenesis via resonant leptogenesis. A singlet fermion (sterile neutrino) with mass $\sim\mathcal{O}$(eV) is also considered, and we are able to put bounds on active-sterile mixing parameters via neutrino oscillation data. Resonant enhancement of lepton asymmetry is studied at TeV scale, where we discuss a few aspects of baryogenesis considering the flavour effects. Possibility of improvement in effective mass from $0\nu\beta\beta$ in the presence of a single generation of sterile neutrino flavour is also studied within the fermion sector. In the scalar sector, the imaginary component of the complex singlet scalar is behaving as a potential dark matter candidate and simultaneously the real part of the complex scalar is associated with the fermion sector for sterile mass generation. A broad region of dark matter mass is analyzed from various annihilation processes, and the VEV of the complex scalar plays a pivotal role to achieve the observed relic density at the right ballpark.