Cobimaximal Mixing with Dirac Neutrinos

TL;DR

This paper derives conditions for cobimaximal mixing in Dirac neutrinos and presents an example model with $A_4$ symmetry and radiative mass generation.

Contribution

It introduces the first conditions for cobimaximal mixing specifically for Dirac neutrinos and provides a concrete $A_4$ symmetric radiative mass model as an example.

Findings

Conditions for cobimaximal mixing in Dirac neutrinos are established.

An explicit $A_4$ symmetric model with radiative Dirac neutrino masses is constructed.

The model achieves $ heta_{23}=rac{ ext{pi}}{4}$ and $ ext{delta}_{CP}= ext{pm}rac{ ext{pi}}{2}$.

Abstract

If neutrinos are Dirac, the conditions for cobimaximal mixing, i.e. $\theta_{23}=\pi/4$ and $\delta_{CP}=\pm \pi/2$ in the $3 \times 3$ neutrino mixing matrix, are derived. One example with $A_4$ symmetry and radiative Dirac neutrino masses is presented.