Chiral properties of the constituent quark model
Abstract
We show that, in a model based exclusively on constituentquark degrees of freedom interacting via a potential, the full axial current is conserved if the spectrum of QbarQ states contains a massless pseudoscalar. The current conservation emerges nonperturbatively if the model satisfies certain constraints on (i) the axial coupling gA of the constituent quark and (ii) the QbarQ potential at large distances. We define the chiral point of the constituent quark model as that set of values of the parameters (such as the masses of the constituent quarks and the couplings in the QbarQ potential) for which the mass of the lowest pseudoscalar QbarQ bound state vanishes. At the chiral point the main signatures of the spontaneously broken chiral symmetry are shown to be present, namely: the axial current is conserved, the decay constants of the excited pseudoscalar bound states vanish, and the pion decay constant has a nonzero value.
 Authors:
 HEPHY, Austrian Academy of Sciences, Nikolsdorfergasse 18, A1050 Vienna (Austria)
 (Russian Federation)
 INFN, Sezione di Roma 3, Via della Vasca Navale 84, I00146, Roma (Italy)
 Publication Date:
 OSTI Identifier:
 21056832
 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), 27 Sep 2006; Other Information: DOI: 10.1063/1.2714395; (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; BOUND STATE; CHIRAL SYMMETRY; CHIRALITY; COUPLING; DEGREES OF FREEDOM; DISTANCE; PARTICLE DECAY; PIONS; POTENTIALS; QUANTUM CHROMODYNAMICS; QUARK MODEL; QUARKANTIQUARK INTERACTIONS; QUARKS; SYMMETRY BREAKING
Citation Formats
Lucha, Wolfgang, Melikhov, Dmitri, Institute of Nuclear Physics, Moscow State University, 119992, Moscow, and Simula, Silvano. Chiral properties of the constituent quark model. United States: N. p., 2007.
Web. doi:10.1063/1.2714395.
Lucha, Wolfgang, Melikhov, Dmitri, Institute of Nuclear Physics, Moscow State University, 119992, Moscow, & Simula, Silvano. Chiral properties of the constituent quark model. United States. doi:10.1063/1.2714395.
Lucha, Wolfgang, Melikhov, Dmitri, Institute of Nuclear Physics, Moscow State University, 119992, Moscow, and Simula, Silvano. Tue .
"Chiral properties of the constituent quark model". United States.
doi:10.1063/1.2714395.
@article{osti_21056832,
title = {Chiral properties of the constituent quark model},
author = {Lucha, Wolfgang and Melikhov, Dmitri and Institute of Nuclear Physics, Moscow State University, 119992, Moscow and Simula, Silvano},
abstractNote = {We show that, in a model based exclusively on constituentquark degrees of freedom interacting via a potential, the full axial current is conserved if the spectrum of QbarQ states contains a massless pseudoscalar. The current conservation emerges nonperturbatively if the model satisfies certain constraints on (i) the axial coupling gA of the constituent quark and (ii) the QbarQ potential at large distances. We define the chiral point of the constituent quark model as that set of values of the parameters (such as the masses of the constituent quarks and the couplings in the QbarQ potential) for which the mass of the lowest pseudoscalar QbarQ bound state vanishes. At the chiral point the main signatures of the spontaneously broken chiral symmetry are shown to be present, namely: the axial current is conserved, the decay constants of the excited pseudoscalar bound states vanish, and the pion decay constant has a nonzero value.},
doi = {10.1063/1.2714395},
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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