QCD equalities for baryon current matrix elements

Journal Article · Wed May 01 04:00:00 EDT 1996 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.53.5115· OSTI ID:284074

Leinweber, D B ^[1]

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1. Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195 (United States)

An examination of the symmetries manifest in the QCD path integral for current matrix elements reveals various equalities among the quark sector contributions. QCD equalities among octet baryon magnetic moments lead to a determination of the disconnected sea-quark contribution to nucleon magnetic moments, which is the most reliable determination in the literature. Matching QCD equalities to recent calculations of decuplet baryon magnetic moments in chiral perturbation theory ({chi}PT) reveals an equivalence between {chi}PT to {ital O}({ital p}{sup 2}) and the simple quark model with an explicit disconnected sea-quark contribution. New insights into SU(3)-flavor symmetry breaking, sea contributions, and constituent quark composition are obtained. The strangeness contribution to nucleon magnetic moments is found to be large at {ital G}{sup {ital s}}{sub {ital M}}(0)={minus}0.75{plus_minus}0.30{mu}{sub {ital N}}. The QCD equalities must be followed by any model which hopes to capture the essence of nonperturbative QCD. Not all models are in accord with these symmetries. {copyright} {ital 1996 The American Physical Society.}

• DOE Contract Number: FG06-88ER40427
• OSTI ID: 284074
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 9 Vol. 53; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BARYONS
CHIRAL SYMMETRY
CURRENTS
MAGNETIC MOMENTS
MATRIX ELEMENTS
NUCLEONS
PERTURBATION THEORY
QUANTUM CHROMODYNAMICS
QUARK MODEL
SU-3 GROUPS
SYMMETRY BREAKING