String Loop Threshold Corrections for N=1 Generalized Coxeter Orbifolds

TL;DR

This paper calculates threshold corrections to gauge couplings in a specific class of N=1 heterotic orbifold models with generalized Coxeter automorphisms, addressing key phenomenological criteria.

Contribution

It provides the first detailed calculation of threshold corrections for non-decomposable abelian (2, 2) symmetric N=1 heterotic orbifolds with generalized Coxeter twists.

Findings

Threshold corrections are computed for the specified orbifold class.

The models satisfy gauge unification and anomaly cancellation criteria.

Results support the phenomenological viability of these orbifold models.

Abstract

We discuss the calculation of threshold corrections to gauge coupling constants for the, only, non-decomposable class of abelian (2, 2) symmetric N=1 four dimensional heterotic orbifold models, where the internal twist is realized as a generalized Coxeter automorphism. The latter orbifold was singled out in earlier work as the only N=1 heterotic $Z_N$ orbifold that satisfy the phenomenological criteria of correct minimal gauge coupling unification and cancellation of target space modular anomalies.