Neutrino seesaw mechanism with texture zeros

TL;DR

This paper systematically analyzes texture zeros in the Type I seesaw mechanism, identifying constraints on neutrino mass matrices and their implications for neutrino properties and decay processes.

Contribution

It classifies standard and nonstandard texture zero constraints in neutrino mass matrices and demonstrates their stability under renormalization group evolution.

Findings

Most constraints can be expressed with simple zero patterns.

Nine classes of nonstandard constraints identified.

Constraints are stable under one-loop renormalization group running.

Abstract

In the context of the Type I seesaw mechanism, we carry out a systematic study of the constraints that result from zeros in both the Dirac and right-handed Majorana neutrino mass matrices. We find that most constraints can be expressed in the standard form with one or two element/cofactor zeros alone, while there are 9 classes of nonstandard constraints. We show that all the constraints are stable under one-loop renormalization group running from the lightest right-handed neutrino mass scale to the electroweak scale. We study the predictions of the nonstandard constraints for the lightest neutrino mass, Dirac CP phase and neutrinoless double beta decay.