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Title: Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the {theta}{sup +} pentaquark

Abstract

Using the exisiting experimental data for hyperon semileptonic decays and the flavor-singlet axial-vector charge g{sub A}{sup (0)} from polarized deep inelastic scattering of the proton, we derive the decay width of the {theta}{sup +} pentaquark baryon. We take into account the effects of flavor SU(3) symmetry breaking within the framework of the chiral quark-soliton model. All dynamical parameters of the model are fixed by using the five experimental hyperon semileptonic decay constants and flavor-singlet axial-vector charge. We obtain the numerical results of the decay width of the {theta}{sup +} pentaquark baryon as a function of the pion-nucleon sigma term {sigma}{sub {pi}}{sub N} and investigate the dependence of the decay width of the {theta}{sup +} on the g{sub A}{sup (0)}, varying the g{sub A}{sup (0)} within the range of the experimental uncertainty. We demonstrate that the combined values of all known semileptonic decays with the generally accepted value of g{sub A}{sup (0)}{approx_equal}0.3 for the proton are compatible with a small decay width {gamma}{sub {theta}}{sub KN} of the {theta}{sup +} pentaquark, i.e. {gamma}{sub {theta}}{sub KN}{<=}1 MeV.

Authors:
;  [1];  [2]
  1. Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)
  2. Department of Physics, and Nuclear Physics and Radiation Technology Institute (NuRI), Pusan National University, 609-735 Busan (Korea, Republic of)
Publication Date:
OSTI Identifier:
21020476
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.75.094004; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; DEEP INELASTIC SCATTERING; FLAVOR MODEL; HYPERONS; MEV RANGE; PARTICLE WIDTHS; PION-NUCLEON INTERACTIONS; PIONS; PROTONS; QUARKS; REST MASS; SEMILEPTONIC DECAY; SOLITONS; SPIN; SU-3 GROUPS

Citation Formats

Yang, Ghil-Seok, Goeke, Klaus, and Kim, Hyun-Chul. Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the {theta}{sup +} pentaquark. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.094004.
Yang, Ghil-Seok, Goeke, Klaus, & Kim, Hyun-Chul. Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the {theta}{sup +} pentaquark. United States. doi:10.1103/PHYSREVD.75.094004.
Yang, Ghil-Seok, Goeke, Klaus, and Kim, Hyun-Chul. Tue . "Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the {theta}{sup +} pentaquark". United States. doi:10.1103/PHYSREVD.75.094004.
@article{osti_21020476,
title = {Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the {theta}{sup +} pentaquark},
author = {Yang, Ghil-Seok and Goeke, Klaus and Kim, Hyun-Chul},
abstractNote = {Using the exisiting experimental data for hyperon semileptonic decays and the flavor-singlet axial-vector charge g{sub A}{sup (0)} from polarized deep inelastic scattering of the proton, we derive the decay width of the {theta}{sup +} pentaquark baryon. We take into account the effects of flavor SU(3) symmetry breaking within the framework of the chiral quark-soliton model. All dynamical parameters of the model are fixed by using the five experimental hyperon semileptonic decay constants and flavor-singlet axial-vector charge. We obtain the numerical results of the decay width of the {theta}{sup +} pentaquark baryon as a function of the pion-nucleon sigma term {sigma}{sub {pi}}{sub N} and investigate the dependence of the decay width of the {theta}{sup +} on the g{sub A}{sup (0)}, varying the g{sub A}{sup (0)} within the range of the experimental uncertainty. We demonstrate that the combined values of all known semileptonic decays with the generally accepted value of g{sub A}{sup (0)}{approx_equal}0.3 for the proton are compatible with a small decay width {gamma}{sub {theta}}{sub KN} of the {theta}{sup +} pentaquark, i.e. {gamma}{sub {theta}}{sub KN}{<=}1 MeV.},
doi = {10.1103/PHYSREVD.75.094004},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}