Neutrino mass matrices with one texture zero and a vanishing neutrino mass

TL;DR

This study analyzes specific neutrino mass matrices with one texture zero and zero mass, revealing which configurations align with current oscillation data and exploring their phenomenological implications.

Contribution

It identifies which one texture zero neutrino mass matrices are compatible with latest data under different mass orderings and constructs models based on Abelian symmetries.

Findings

All six classes ruled out for normal mass ordering with m_1=0.

Four classes compatible with inverted ordering at 3σ.

Two classes compatible at 1σ confidence level.

Abstract

Assuming Majorana nature of neutrinos, we investigate the singular one texture zero neutrino mass matrices in the flavor basis. We find that for the normal mass ordering with $m_1=0$, all the six one texture zero classes are now ruled out at 3$\sigma$ confidence level, whereas for inverted mass ordering with $m_3=0$ only four classes out of total six can accommodate the latest neutrino oscillation data at 3$\sigma$ confidence level. Moreover, only two classes can accommodate the present data at 1$\sigma$ confidence level. We examine the phenomenological implications of the allowed classes for the effective Majorana mass, Dirac and Majorana CP-violating phases. Working within the framework of type-I seesaw mechanism, we present simple discrete Abelian symmetry models leading to all the phenomenologically allowed classes.