Dirac neutrinos from flavor symmetry

TL;DR

This paper proposes a flavor symmetry-based model where neutrinos are Dirac particles with small Yukawa couplings, fitting current oscillation data and linking atmospheric mixing angle octant to the lightest neutrino mass.

Contribution

It introduces a novel flavor symmetry model that forbids Majorana masses, resulting in Dirac neutrinos with specific correlations between mixing angles and neutrino mass hierarchy.

Findings

Model fits current neutrino oscillation data

Correlates atmospheric angle octant with lightest neutrino mass

Maximal mixing is excluded for any neutrino mass

Abstract

We present a model where Majorana neutrino mass terms are forbidden by the flavor symmetry group Delta(27). Neutrinos are Dirac fermions and their masses arise in the same way as that of the charged fermions, due to very small Yukawa couplings. The model fits current neutrino oscillation data and correlates the octant of the atmospheric angle with the magnitude of the lightest neutrino mass, with maximal mixing excluded for any neutrino mass