Neutrino mu-tau reflection symmetry and its breaking in the minimal seesaw

TL;DR

This paper explores the implementation and breaking of mu-tau reflection symmetry in the minimal seesaw model, analyzing its implications for neutrino mixing angles, CP phases, and leptogenesis.

Contribution

It introduces a framework for embedding mu-tau reflection symmetry into the minimal seesaw and investigates the phenomenological effects of its breaking.

Findings

Symmetry predicts specific neutrino mixing angles and phases.

Breaking the symmetry can account for experimental deviations.

Implications for leptogenesis mechanisms are discussed.

Abstract

In this paper, we attempt to implement the neutrino $\mu$-$\tau$ reflection symmetry (which predicts $\theta^{}_{23} = \pi/4$ and $\delta = \pm \pi/2$ as well as trivial Majorana phases) in the minimal seesaw (which enables us to fix the neutrino masses). For some direct (the preliminary experimental hints towards $\theta^{}_{23} \neq \pi/4$ and $\delta \neq - \pi/2$) and indirect (inclusion of the renormalization group equation effect and implementation of the leptogenesis mechanism) reasons, we particularly study the breakings of this symmetry and their phenomenological consequences.