Superheavy spectrum and supersymmetric grand unification
- Department of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)
- Superconducting Super Collider Laboratory, 2550 Beckleymeade Avenue, Dallas, Texas 75237 (United States)
We examine in detail the effect of the superheavy particle spectrum on the claim that recent data from CERN LEP are consistent with a SUSY SU(5) grand unified theory (GUT) whose superparticle spectrum is characterized by a single scale [ital M][sub [ital S]] of approximately 1 TeV, and has three couplings unifying at a scale [mu]=[ital M][sub [ital V]]. Using the most recent LEP determination of [alpha][sub [ital s]], 0.125[plus minus]0.005, we find that SUSY unification requires that [ital M][sub [ital S]][lt]100 GeV. Larger values of [ital M][sub [ital S]] can be accommodated by assuming that [Sigma], a multiplet transforming as the adjoint of SU(5), has a mass 8 to 12 orders of magnitude below the GUT scale, with the GUT scale close to or even above the Planck scale. Larger values of [alpha][sub [ital s]], with unification below the Planck scale, may be accommodated only by breaking the degeneracy of the color octet and weak triplets of the [Sigma] multiplet, but this splitting appears in SUSY SU(5) GUT's only as a gravitational effect in the form of nonrenormalizable operators.
- DOE Contract Number:
- AC35-89ER40486
- OSTI ID:
- 6583634
- Journal Information:
- Physical Review, D (Particles Fields); (United States), Vol. 47:11; ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
Supergravity grand unification, proton decay and cosmological constraints
Probing the grand-unification-scale mass spectrum through precision measurements on the weak-scale parameters
Related Subjects
Pa
GRAND UNIFIED THEORY
COUPLING CONSTANTS
MASS FORMULAE
PARTICLE MULTIPLETS
SU-5 GROUPS
SUPERSYMMETRY
FIELD THEORIES
LIE GROUPS
MATHEMATICAL MODELS
MULTIPLETS
PARTICLE MODELS
SU GROUPS
SYMMETRY
SYMMETRY GROUPS
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
662210* - Specific Theories & Interaction Models
Particle Systematics- Unified Theories & Models- (1992-)
662120 - General Theory of Particles & Fields- Symmetry
Conservation Laws
Currents & Their Properties- (1992-)