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Title: Parity doublers in chiral potential quark models

Abstract

The effect of spontaneous breaking of chiral symmetry over the spectrum of highly excited hadrons is addressed in the framework of a microscopic chiral potential quark model (Generalised Nambu-Jona-Lasinio model) with a vectorial instantaneous quark kernel of a generic form. A heavy-light quark-antiquark bound system is considered, as an example, and the Lorentz nature of the effective light-quark potential is identified to be a pure Lorentz-scalar, for low-lying states in the spectrum, and to become a pure spatial Lorentz vector, for highly excited states. Consequently, the splitting between the partners in chiral doublets is demonstrated to decrease fast in the upper part of the spectrum so that neighboring states of an opposite parity become almost degenerate. A detailed microscopic picture of such a 'chiral symmetry restoration' in the spectrum of highly excited hadrons is drawn and the corresponding scale of restoration is estimated.

Authors:
;  [1];  [2]
  1. Institute of Theoretical and Experimental Physics, 117218, B.Cheremushkinskaya 25, Moscow (Russian Federation)
  2. Centro de Fisica das Interaccoes Fundamentais (CFIF), Departamento de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais, P-1049-001 Lisboa (Portugal)
Publication Date:
OSTI Identifier:
21056834
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 892; Journal Issue: 1; Conference: QCHS7: 7. conference on quark confinement and the hadron spectrum, Ponta Delgada, Acores (Portugal), 2-7 Sep 2006; Other Information: DOI: 10.1063/1.2714397; (c) 2007 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; ANTIQUARKS; CHIRAL SYMMETRY; CHIRALITY; D QUARKS; EXCITED STATES; HADRONS; PARITY; POTENTIALS; QUANTUM CHROMODYNAMICS; QUARK MODEL; SYMMETRY BREAKING; U QUARKS

Citation Formats

Kalashnikova, Yu. S., Nefediev, A. V., and Ribeiro, J. E. F. T.. Parity doublers in chiral potential quark models. United States: N. p., 2007. Web. doi:10.1063/1.2714397.
Kalashnikova, Yu. S., Nefediev, A. V., & Ribeiro, J. E. F. T.. Parity doublers in chiral potential quark models. United States. doi:10.1063/1.2714397.
Kalashnikova, Yu. S., Nefediev, A. V., and Ribeiro, J. E. F. T.. Tue . "Parity doublers in chiral potential quark models". United States. doi:10.1063/1.2714397.
@article{osti_21056834,
title = {Parity doublers in chiral potential quark models},
author = {Kalashnikova, Yu. S. and Nefediev, A. V. and Ribeiro, J. E. F. T.},
abstractNote = {The effect of spontaneous breaking of chiral symmetry over the spectrum of highly excited hadrons is addressed in the framework of a microscopic chiral potential quark model (Generalised Nambu-Jona-Lasinio model) with a vectorial instantaneous quark kernel of a generic form. A heavy-light quark-antiquark bound system is considered, as an example, and the Lorentz nature of the effective light-quark potential is identified to be a pure Lorentz-scalar, for low-lying states in the spectrum, and to become a pure spatial Lorentz vector, for highly excited states. Consequently, the splitting between the partners in chiral doublets is demonstrated to decrease fast in the upper part of the spectrum so that neighboring states of an opposite parity become almost degenerate. A detailed microscopic picture of such a 'chiral symmetry restoration' in the spectrum of highly excited hadrons is drawn and the corresponding scale of restoration is estimated.},
doi = {10.1063/1.2714397},
journal = {AIP Conference Proceedings},
number = 1,
volume = 892,
place = {United States},
year = {Tue Feb 27 00:00:00 EST 2007},
month = {Tue Feb 27 00:00:00 EST 2007}
}
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