Electromagnetic structure of octet baryons

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Physical Review, D (Particles Fields); (USA)

DOI:https://doi.org/10.1103/PhysRevD.43.1659· OSTI ID:6202307

Leinweber, D B; Woloshyn, R M ^[1]; Draper, T ^[2]

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1. TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T2A3 (CA)
2. University of Kentucky, Lexington, Kentucky 40506 (US)

A numerical simulation of quenched QCD on a 24{times}12{times}12{times}24 lattice at {beta}=5.9 is used to calculate the electric and magnetic form factors of the baryon octet. General forms of the baryon interpolating fields are considered. Magnetic moments, electric radii, magnetic radii, and magnetic transition moments are extracted from the form factors. The electric properties are found to be consistent with a quark-model picture involving spin-dependent forces. The lattice results for the magnetic properties show a mass and spin dependence of the effective quark moments which is not accounted for in conventional quark models. Lattice calculations underestimate the magnitude of electric radii, magnetic radii, and magnetic moments compared to experimental measurements. The finite volume of the periodic lattice may be responsible for the discrepancies. The pattern of electromagnetic radii in the lattice results are seen to be generally reproduced in the model results that are considered. The only exception is that of {Xi}{sup {minus}} which proves to be a sensitive probe of the quark dynamics. Lattice calculations indicate a positive value for the normalized square magnetic radius in {Xi}{sup {minus}} which contrasts Skyrme model results. Ratios of the magnetic moments allow a more detailed comparison with the experimental measurements. The lattice calculations are seen to better reproduce the experimental ratios than the model calculations.

• DOE Contract Number: FG05-84ER40154
• OSTI ID: 6202307
• Journal Information: Physical Review, D (Particles Fields); (USA), Journal Name: Physical Review, D (Particles Fields); (USA) Vol. 43:5; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

645202* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Electromagnetic Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR MOMENTUM
BARYONS
COMPOSITE MODELS
CORRELATION FUNCTIONS
DIFFERENTIAL EQUATIONS
DIRAC EQUATION
ELECTROMAGNETIC FORM FACTORS
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FIELD THEORIES
FORM FACTORS
FUNCTIONS
HADRONS
LATTICE FIELD THEORY
MAGNETIC MOMENTS
MASS
MATHEMATICAL MODELS
NUCLEON-NUCLEON POTENTIAL
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE MODELS
PARTICLE PROPERTIES
PARTICLE RADII
PERTURBATION THEORY
POTENTIALS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MODEL
SKYRME POTENTIAL
SPIN
SUM RULES
WAVE EQUATIONS