Levels of U(1)y in Minimal String Model on Z(N)*Z(M) Orbifolds

Abstract

We study a minimal string model possessing the same massless spectra as the MSSM on $Z_N\times Z_M$ orbifolds. Threshold corrections of the gauge coupling constants of SU(3), SU(2) and U(1)${}_Y$ are investigated in a case of an overall modulus. Using computer analyses, we search ranges of levels of U(1)${}_Y$ allowed by the LEP experiments. It is found that $Z_3\times Z_3$ can not derive the minimal string model for a $M_Z$ SUSY breaking scale. The minimum values of the overall moduli are estimated within the ranges of the levels.

14 pages, KANAZAWA-93-12, Latex file

References in corpus (2)

• Duality Anomaly Cancellation, Minimal String Unification and the Effective Low-Energy Lagrangian of 4-D Strings
• Gauge Coupling Unification in Superstring Derived Standard--like Models

Cited by in corpus (9)

• Non-universal Soft Scalar Masses in Superstring Theories
• Soft Scalar Masses in String Models with Anomalous $U(1)$ symmetry
• Running of Soft Parameters in Extra Space-Time Dimensions
• Generic Formula of Soft Scalar Masses in String Models
• Selection Rules for Nonrenormalizable Couplings in Superstring Theories
• Minimal String Unification and Constraint on Hidden Sector
• Discrete R-symmetry anomalies in heterotic orbifold models
• Threshold corrections in orbifold models and superstring unification of gauge interactions
• Light adjoint scalars and unification at the string scale