Searching singlet extensions of the supersymmetric standard model in $ Z_{6-II}$ orbifold compactification of heterotic string

TL;DR

This paper explores supersymmetric standard model realizations with extra singlets and U(1) symmetries derived from heterotic string compactification on a specific orbifold, analyzing vacuum stabilization and superpotential constraints.

Contribution

It presents a detailed analysis of vacuum stabilization and superpotential structures in heterotic string models with extra singlets and U(1)s, including automated selection of semi-realistic vacua.

Findings

Identification of vacua with massless Higgs and singlet pairs

Decoupling of exotic color triplets to suppress B and L violation

Compatibility of superpotential with string selection rules

Abstract

We search for supersymmetric standard model realizations with extra singlets and extra $ U(1)$ using the heterotic string compactification on the $ Z_{6-II}$ orbifold with two Wilson lines. We analyze the vacuum restabilization mechanism for three representative Pati-Salam string models obtained in the literature and present detailed results for the effective superpotential compatible with the string selection rules. An automated selection of semi-realistic vacua along flat directions in the non-Abelian singlet modes field space is performed by requiring the presence of massless pairs of electroweak Higgs bosons having trilinear superpotential couplings with massless singlet modes and the decoupling of color triplet exotic modes needed to suppress $B $ and $ L $ number violating processes.