On flavor symmetries of phenomenologically viable string compactifications

TL;DR

This paper investigates the origin and structure of flavor symmetries in heterotic orbifold string compactifications, identifying common non-Abelian symmetries and exploring their phenomenological implications.

Contribution

It systematically determines the most frequent non-Abelian flavor symmetries in Abelian heterotic orbifolds and examines their potential for particle physics phenomenology.

Findings

D_4 and Delta(54) are the most common non-Abelian flavor symmetries.

Many models exhibit purely Abelian flavor symmetries.

A sample model with Delta(54) shows promising phenomenological features.

Abstract

Heterotic orbifolds can explain the origin of flavor symmetries and the flavor representations of matter fields in particle physics as a result of the geometric properties of the associated string states in the compact space. After a review of the method to obtain flavor symmetries in these models, we determine the most frequent non-Abelian flavor symmetries appearing in promising Abelian heterotic orbifolds. Interestingly, these symmetries correspond only to D_4, Delta(54) and products of these symmetries and Abelian factors. A large set of promising models exhibits purely Abelian flavor symmetries. We finally explore the phenomenological potential of a sample model endowed with Delta(54) assuming certain ad hoc flavon expectation values.