Weak scale measurement constraints on string models

Journal Article · Wed Jun 15 00:00:00 EDT 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.49.6656· OSTI ID:7308596

Xiu, R ^[1]

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1. Department of Physics, University of California and Physics Division, Lawrence Berkeley Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

The result of the modular-invariant one-loop string effective coupling constant for a large class of models is used to discuss the weak scale measurement constraints on superstring models. Superstring models with intermediate gauge symmetry breaking are proposed to account for the grand gauge unification scale [ital M][sub GUT]=10[sup 16] GeV, which is deduced from the precision weak scale measurement in the minimal SUSY unification model. A gaugino-condensation-induced Hosotani mechanism is suggested for the intermediate gauge symmetry breaking. In this scheme, supergravity, gauge symmetry, and space-time compactification are induced by one nonperturbative dynamics: gaugino condensation. The string scale [mu][sub [ital s]] is calculated in intermediate SU(5) string models. A relation between the intermediate gauge symmetry-breaking scale [ital M][sub [ital I]]=[ital M][sub GUT] and string scale is found to be [mu][sub [ital s]][sup 3]=[ital M][sub [ital I]][ital m][sub [ital P]][sup 2]. It is argued that this relation is a general result for all the superstring models with intermediate gauge symmetry breaking. The level one minimal SUSY left-right string models are shown to be excluded by weak scale measurement. The constraints on the ratio of affine levels is worked out. It is demonstrated that string unification is more restricted by the experiments than any other unification schemes are.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 7308596
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 49:12; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Pa
SUPERSTRING MODELS
CONSTRAINTS
COMPACTIFICATION
COUPLING CONSTANTS
GAUGE INVARIANCE
GRAND UNIFIED THEORY
SPACE-TIME
SUPERGRAVITY
SYMMETRY BREAKING
COMPOSITE MODELS
EXTENDED PARTICLE MODEL
FIELD THEORIES
INVARIANCE PRINCIPLES
MATHEMATICAL MODELS
PARTICLE MODELS
QUARK MODEL
STRING MODELS
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
662110* - General Theory of Particles & Fields- Theory of Fields & Strings- (1992-)
662120 - General Theory of Particles & Fields- Symmetry
Conservation Laws
Currents & Their Properties- (1992-)
662210 - Specific Theories & Interaction Models
Particle Systematics- Unified Theories & Models- (1992-)