New textures for the lepton mass matrices

TL;DR

This paper explores specific zero-texture patterns in lepton mass matrices, predicting an inverted neutrino mass hierarchy, a sum near 0.1 eV, and particular CP-violating phase values, with implications for neutrinoless double-beta decay.

Contribution

It identifies viable zero-texture patterns in lepton mass matrices that lead to specific predictions for neutrino properties and decay processes.

Findings

Neutrino mass spectrum is inverted.

Sum of light-neutrino masses is close to 0.1 eV.

Neutrinoless double-beta decay mass term is between 12 and 22 meV.

Abstract

We study predictive textures for the lepton mass matrices in which the charged-lepton mass matrix has either four or five zero matrix elements while the neutrino Majorana mass matrix has, respectively, either four or three zero matrix elements. We find that all the viable textures of these two kinds share many predictions: the neutrino mass spectrum is inverted, the sum of the light-neutrino masses is close to 0.1 eV, the Dirac phase $\delta$ in the lepton mixing matrix is close to either $0$ or $\pi$, and the mass term responsible for neutrinoless double-beta decay lies in between 12 and 22 meV.