Revisiting the two-zero texture Majorana neutrino mass matrix

TL;DR

This paper updates the analysis of two-zero texture Majorana neutrino mass matrices using recent data, finding that most are compatible with current constraints but some could be ruled out by future experiments.

Contribution

It provides an updated comprehensive analysis of all seven two-zero textures with latest oscillation, cosmology, and decay data, highlighting which are still viable.

Findings

All seven textures are compatible with recent oscillation data.

Five textures with nonzero 1-1 entry are in tension with cosmology and decay constraints.

Future experiments could rule out or severely constrain some textures.

Abstract

It has long been pointed out that there are seven different two-zero texture neutrino mass matrices compatible with neutrino oscillation data. We perform an updated analysis with the recently published Nu-Fit 6.0 results. We also subject the seven two-zero textures to constraints on neutrino mass from cosmology, end point of beta decay spectrum, and neutrinoless double beta decay experiments. We find that all seven textures are compatible with the new oscillation parameters. However, we find five textures, whose 1-1 entry is nonvanishing, are in severe tension with the constraints from cosmology and neutrinoless double beta decay. With the next generation experiments, these five textures could be decisively ruled out. For the remaining two textures, one of them could be ruled out, or severely constrained, if the octant of $\theta_{23}$ is determined.