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Title: Chiral symmetry patterns of excited mesons with the Coulomb-like linear confinement

Abstract

The spectrum of qq mesons in a model where the only interaction is a linear Coulomb-like instantaneous confining potential is studied. The single-quark Green function as well as the dynamical chiral symmetry breaking are obtained from the Schwinger-Dyson (gap) equation. Given the dressed quark propagator, a complete spectrum of 'usual' mesons is obtained from the Bethe-Salpeter equation. The spectrum exhibits restoration of chiral and U(1){sub A} symmetries at large spins and/or radial excitations. This property is demonstrated both analytically and numerically. At large spins and/or radial excitations higher degree of degeneracy is observed, namely, all states with the given spin fall into reducible representations [(0,1/2)+(1/2,0)]x[(0,1/2)+(1/2,0)] that combine all possible chiral multiplets with the given J and n. The structure of the meson wave functions as well as the form of the angular and radial Regge trajectories are investigated.

Authors:
;  [1]
  1. Institute for Physics, Theoretical Physics branch, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria)
Publication Date:
OSTI Identifier:
21011021
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.036007; (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; BETHE-SALPETER EQUATION; BIOLOGICAL RECOVERY; CHIRAL SYMMETRY; CHIRALITY; EXCITATION; GREEN FUNCTION; MESONS; MULTIPLETS; POTENTIALS; PROPAGATOR; QUARKS; REGGE TRAJECTORIES; SPIN; SYMMETRY BREAKING; U-1 GROUPS; WAVE FUNCTIONS

Citation Formats

Wagenbrunn, R. F., and Glozman, L. Ya.. Chiral symmetry patterns of excited mesons with the Coulomb-like linear confinement. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.036007.
Wagenbrunn, R. F., & Glozman, L. Ya.. Chiral symmetry patterns of excited mesons with the Coulomb-like linear confinement. United States. doi:10.1103/PHYSREVD.75.036007.
Wagenbrunn, R. F., and Glozman, L. Ya.. Thu . "Chiral symmetry patterns of excited mesons with the Coulomb-like linear confinement". United States. doi:10.1103/PHYSREVD.75.036007.
@article{osti_21011021,
title = {Chiral symmetry patterns of excited mesons with the Coulomb-like linear confinement},
author = {Wagenbrunn, R. F. and Glozman, L. Ya.},
abstractNote = {The spectrum of qq mesons in a model where the only interaction is a linear Coulomb-like instantaneous confining potential is studied. The single-quark Green function as well as the dynamical chiral symmetry breaking are obtained from the Schwinger-Dyson (gap) equation. Given the dressed quark propagator, a complete spectrum of 'usual' mesons is obtained from the Bethe-Salpeter equation. The spectrum exhibits restoration of chiral and U(1){sub A} symmetries at large spins and/or radial excitations. This property is demonstrated both analytically and numerically. At large spins and/or radial excitations higher degree of degeneracy is observed, namely, all states with the given spin fall into reducible representations [(0,1/2)+(1/2,0)]x[(0,1/2)+(1/2,0)] that combine all possible chiral multiplets with the given J and n. The structure of the meson wave functions as well as the form of the angular and radial Regge trajectories are investigated.},
doi = {10.1103/PHYSREVD.75.036007},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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