Two-loop calculations of M/sub b//M/sub tau/ and heavy-fermion masses in the SU(5) model

Journal Article · Fri Jul 01 04:00:00 EDT 1983 · Phys. Rev. D; (United States)

DOI:https://doi.org/10.1103/PhysRevD.28.194· OSTI ID:5835530

Oliensis, J; Fischler, M

Two-loop calculations of M/sub b//M/sub tau/ and M/sub s/ in the SU(5) model for 3--5 generations are presented, based on the complete SU(3) x SU(2) x U(1) two-loop Higgs-Yukawa ..beta.. function. We find that the observed M/sub b//M/sub tau/ is consistent with three and four generations, in contrast to earlier work, but probably not with five. However if ..lambda../sub MS/ is large (where MS refers to the modified minimal-subtraction scheme), as may be required to explain the nonobservation of proton decay, the predicted M/sub b/ may be inconsistent with experiment even for three generations. We find upper limits on the top-quark mass from the requirement that M/sub b//M/sub tau/ not be too large. We redo earlier calculations of M/sub X/ and sin/sup 2/theta/sub W/, assuming the existence of heavy fermions, and essentially are in agreement with them. Lastly we consider the possibility of predicting the masses of heavy fermions by means of ''pseudofixed points'' of the Higgs-Yukawa renormalization-group equations.

• Research Organization: Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510
• OSTI ID: 5835530
• Journal Information: Phys. Rev. D; (United States), Journal Name: Phys. Rev. D; (United States) Vol. 28:1; ISSN PRVDA
• Country of Publication: United States
• Language: English

Related Subjects

645201* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- General & Scattering Theory
645400 -- High Energy Physics-- Field Theory
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
FERMIONS
HIGGS MODEL
LIE GROUPS
MASS FORMULAE
MATHEMATICAL MODELS
PARTICLE MODELS
RENORMALIZATION
SU GROUPS
SU-2 GROUPS
SU-3 GROUPS
SU-5 GROUPS
SYMMETRY BREAKING
SYMMETRY GROUPS
U GROUPS
U-1 GROUPS
UNIFIED GAUGE MODELS