Translational invariance and soliton models of the nucleon

Journal Article · Tue Nov 01 04:00:00 EST 1983 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.28.2042· OSTI ID:5336082

Celenza, L S; Shakin, C M

We present a relativistic model of nucleon structure which places particular emphasis on translational invariance. An analysis of the field equations of the Friedberg-Lee soliton model is presented which avoids the static approximation. The matrix element of the quark-field operator between a nucleon state and a ''diquark'' state is written in terms of a quark wave function, and an equation which determines this wave function is given. We do not solve this equation here. Instead, we introduce a simple parametrization of the quark wave functions and proceed to calculate various nucleon observables. We present a calculation of nucleon electromagnetic form factors using a vector dominance model. We also calculate the axial current form factors and discuss the Goldberger-Treiman and partially-conserved axial vector current relations in our model. In our calculations the nucleon magnetic moment is given as the sum of three terms: a recoil moment, a confinement moment, and a mesonic term, the latter term contributing about 50 percent of the proton (or neutron) moment. We find that the recoil part of the proton moment is equal to (3/5)g/sub A/, where g/sub A/ is the ratio of the axial vector coupling constants, g/sub A/ = G/sub A//G/sub V/. Other models of the nucleon moment usually stress only one aspect of the calculation. For example, in the (static-cavity) MIT bag models the moment is entirely a ''confinement moment,'' the calculated moment being proportional to the confinement radius. In nonrelativistic quark models the quarks are assigned an anomalous magnetic moment and the entire nucleon moment is explained on that basis; in our calculations the analogous contribution to the magnetic moment, the ''mesonic term,'' contributes only about 50 percent of the total moment, as noted above.

• Research Organization: Department of Physics and Institute for Nuclear Theory, Brooklyn College of the City University of New York, Brooklyn, New York 11210
• OSTI ID: 5336082
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 28:5; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

645201* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- General & Scattering Theory
645202 -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Electromagnetic Interactions & Properties
645206 -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions
Baryon No. = 1-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BAG MODEL
BARYONS
COMPOSITE MODELS
ELECTROMAGNETIC FORM FACTORS
ELEMENTARY PARTICLES
EQUATIONS
EXTENDED PARTICLE MODEL
FERMIONS
FIELD EQUATIONS
FORM FACTORS
FUNCTIONS
GLUONS
HADRONS
MAGNETIC MOMENTS
MATHEMATICAL MODELS
MATRIX ELEMENTS
NUCLEONS
PARTICLE MODELS
PARTICLE PROPERTIES
PARTICLE STRUCTURE
POSTULATED PARTICLES
QUARK MODEL
QUASI PARTICLES
SOLITONS
VECTOR DOMINANCE MODEL
WAVE FUNCTIONS