SO(3) family symmetry and axions

TL;DR

This paper explores a gauged SO(3) flavor symmetry extension of the Standard Model, incorporating right-handed neutrinos and a Peccei-Quinn symmetry, to explain fermion masses, mixings, and solve the strong CP problem.

Contribution

It introduces a novel SO(3) flavor symmetry model with Peccei-Quinn symmetry that unifies fermion mass relations and neutrino properties.

Findings

Successfully reproduces observed fermion masses and mixings

Establishes a characteristic relation among fermion parameters

Provides a framework addressing the strong CP problem

Abstract

Motivated by the idea of comprehensive unification, we study a gauged SO(3) flavor extension of the extended Standard Model, including right-handed neutrinos and a Peccei-Quinn symmetry with simple charge assignments. The model accommodates the observed fermion masses and mixings and yields a characteristic, successful relation among them. The Peccei-Quinn symmetry is an essential ingredient.