Theoretical and experimental review of the weak neutral current: a determination of its structure and limits on deviations from the minimal SU(2)/sub L/ x U(1) electroweak theory

Journal Article · Wed Apr 01 00:00:00 EST 1981 · Rev. Mod. Phys.; (United States)

DOI:https://doi.org/10.1103/RevModPhys.53.211· OSTI ID:6616240

Kim, J E; Langacker, P; Levine, M; Williams, H H

A detailed analysis of existing neutral-current data has been performed in order (a) to determine as fully as possible the structure of the hadronic and leptonic neutral currents without recourse to a specific weak-interaction model; (b) to search for the effects of small deviations from the Weinberg-Salam (WS-GIM) model; and (c) to determine the value of sin/sup 2/theta/sub w/ as accurately as possible. The authors attempt to incorporate the best possible theoretical expressions in the treatment of each of the reactions. For deep-inelastic scattering, for example, the effects of quantum chromodynamics, including the contributions of the s and c quarks, have been included. The sensitivity of the results both to systematic uncertainties in the data and to theoretical uncertainties in the treatment of deep-inelastic scattering, semi-inclusive pion production, ..nu.. elastic scattering from protons, and the asymmetry in polarized eD scattering have been considered; the systematic errors are generally found to be smaller than the statistical uncertainties. In the model-independent analyses the authors find that the hadronic neutral-current parameters are uniquely determined to lie within a small domain consistent with the WS-GIM model. The leptonic couplings are determined to within a twofold ambiguity; one solution, the axial-vector-dominant, is consistent with the WS-GIM model. If factorization is assumed then the axial-dominant solution is uniquely determined and null atomic parity violation experiments are inconsistent with other neutral-current experiments. Within generalized SU(2) x U(1) models we find the following limits on mixing between right-handed singlets and doublets: sin/sup 2/..cap alpha../sub u/< or =0.103, sin/sup 2/..cap alpha../sub d/< or =0.348, and sin/sup 2/..cap alpha../sub e/< or =0.064.

• Research Organization: Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104
• DOE Contract Number: EY-76-02-3071
• OSTI ID: 6616240
• Journal Information: Rev. Mod. Phys.; (United States), Vol. 53:2
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
LEPTON-HADRON INTERACTIONS
NEUTRAL-CURRENT INTERACTIONS
WEAK NEUTRAL CURRENTS
REVIEWS
CABIBBO ANGLE
COUPLING CONSTANTS
DEEP INELASTIC SCATTERING
DISTRIBUTION FUNCTIONS
NEUTRINO-DEUTERON INTERACTIONS
P INVARIANCE
SEMI-INCLUSIVE INTERACTIONS
SU-2 GROUPS
U-1 GROUPS
WEINBERG-SALAM GAUGE MODEL
ALGEBRAIC CURRENTS
CURRENTS
DOCUMENT TYPES
FUNCTIONS
INCLUSIVE INTERACTIONS
INELASTIC SCATTERING
INTERACTIONS
INVARIANCE PRINCIPLES
LEPTON-BARYON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
LIE GROUPS
MATHEMATICAL MODELS
NEUTRAL CURRENTS
PARTICLE INTERACTIONS
PARTICLE MODELS
SCATTERING
SU GROUPS
SYMMETRY GROUPS
U GROUPS
UNIFIED GAUGE MODELS
645102* - High Energy Physics- Particle Interactions &amp; Properties-Experimental- Weak Interactions &amp; Properties
645203 - High Energy Physics- Particle Interactions &amp; Properties-Theoretical- Weak Interactions &amp; Properties