Models of maximal atmospheric neutrino mixing

TL;DR

This paper reviews models of neutrino mass matrices that naturally produce maximal atmospheric mixing, focusing on symmetry-based approaches within the seesaw mechanism and scalar sector extensions.

Contribution

It introduces and compares three models that generate maximal atmospheric neutrino mixing angles through symmetry principles and specific mass matrix structures.

Findings

Two types of neutrino mass matrices yield maximal atmospheric mixing.

Three models based on symmetries successfully produce the desired mixing angle.

The models utilize the seesaw mechanism and scalar sector extensions.

Abstract

We discuss two types of neutrino mass matrices which both give $\theta_{23} = 45^\circ$, i.e., a maximal atmospheric mixing angle. We review three models, based on the seesaw mechanism and on simple extensions of the scalar sector of the Standard Model, where those mass matrices are obtained from symmetries.