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Title: PentaQuark Mass and Structure

Abstract

The Quark Delocalization, Color Screening Model has successfully reproduced the binding energy and structure of 9- and 12-quark systems that are small nuclei, namely 3He and 4He, in a relativistic version. In a non-relativistic version it has successfully been applied to 6-quark systems to describe baryon-baryon potentials, phase shifts and cross sections. It is applied here to KN molecular, Jaffe-Wilczek, Karliner-Lipkin and tetrahedral structures proposed for the reported pentaquark state, {theta}+. In this model, we find that the excitation energy above KN threshold can be reproduced in some cases. The negative parity state is always found at a lower mass than the positive parity one. Concerns regarding additional physics effects which may obviate this result and a conjecture regarding two- vs. three-body final state production of the {theta}+ are also noted.

Authors:
 [1];  [2];  [3];  [4]
  1. Theoretical Division, LANL, Los Alamos, NM87545 (United States)
  2. Center for Theoretical Physics, Nanjing University, Nanjing, 210093 (China)
  3. Department of Physics, Nanjing Normal University, Nanjing, 210097 (China)
  4. CERN, Ch-1211 Geneva 23 (Switzerland)
Publication Date:
OSTI Identifier:
20798087
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 814; Journal Issue: 1; Conference: 11. international conference on hadron spectroscopy, Rio de Janeiro (Brazil), 21-26 Aug 2005; Other Information: DOI: 10.1063/1.2176500; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BARYON-BARYON INTERACTIONS; BINDING ENERGY; COLOR MODEL; CROSS SECTIONS; EXCITATION; HELIUM 3; HELIUM 4; PARITY; PHASE SHIFT; QUARKS; RELATIVISTIC RANGE; REST MASS; THREE-BODY PROBLEM

Citation Formats

Goldman, T., Wang, Fan, Ping Jialun, and Qing Di. PentaQuark Mass and Structure. United States: N. p., 2006. Web. doi:10.1063/1.2176500.
Goldman, T., Wang, Fan, Ping Jialun, & Qing Di. PentaQuark Mass and Structure. United States. doi:10.1063/1.2176500.
Goldman, T., Wang, Fan, Ping Jialun, and Qing Di. Sat . "PentaQuark Mass and Structure". United States. doi:10.1063/1.2176500.
@article{osti_20798087,
title = {PentaQuark Mass and Structure},
author = {Goldman, T. and Wang, Fan and Ping Jialun and Qing Di},
abstractNote = {The Quark Delocalization, Color Screening Model has successfully reproduced the binding energy and structure of 9- and 12-quark systems that are small nuclei, namely 3He and 4He, in a relativistic version. In a non-relativistic version it has successfully been applied to 6-quark systems to describe baryon-baryon potentials, phase shifts and cross sections. It is applied here to KN molecular, Jaffe-Wilczek, Karliner-Lipkin and tetrahedral structures proposed for the reported pentaquark state, {theta}+. In this model, we find that the excitation energy above KN threshold can be reproduced in some cases. The negative parity state is always found at a lower mass than the positive parity one. Concerns regarding additional physics effects which may obviate this result and a conjecture regarding two- vs. three-body final state production of the {theta}+ are also noted.},
doi = {10.1063/1.2176500},
journal = {AIP Conference Proceedings},
number = 1,
volume = 814,
place = {United States},
year = {Sat Feb 11 00:00:00 EST 2006},
month = {Sat Feb 11 00:00:00 EST 2006}
}
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  • The Regge exchange model used by Dzierba et al. is shown to be questionable, since the pion pole term is not allowed. Hence the Regge amplitudes in their calculation are exaggerated. The amount of kinematic reflection in the mass spectrum of the (nK+) system, which is one decay channel of a possible pentaquark, is not well justified in the fitting procedure used by Dzierba et al., as shown by comparison with the (K+K-) invariant mass spectrum, which is one decay channel of the a{sub 2} and f{sub 2} tensor mesons. While kinematic reflections are still a concern in some papersmore » that have presented evidence for the pentaquark, better quantitative calculations are needed to demonstrate the significance of this effect.« less