Scalar Mesons As A Mixing Of Two And Four Quark States
Abstract
The scalar mesons are a puzzling problem in meson spectroscopy: they appear to be too numerous and with a mass often incompatible with usual quark-quark potentials. In this paper, we study the possibility to describe them as a mixing of states composed of one and two quark-antiquark pairs. A potential containing confinement, gluon exchange and boson exchange, as expected from chiral symmetry, is used in a consistent way to calculate the two and four quark states separately. Then, a coupling between these states is introduced as a constant term depending only on the flavour of the created pair. The description is largely improved. To refine the treatment, a coupling with a glueball is also considered. All the experimental resonances seem to fit correctly in this scheme.
- Authors:
- LPSC, 53 Avenue des martyrs, F38026 Grenoble Cedex (France)
- Grupo de Fisica Nuclear, Universidad de Salamanca, E37008 Salamanca (Spain)
- Publication Date:
- OSTI Identifier:
- 20798153
- 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: 10.1063/1.2176561; (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; BOSON-EXCHANGE MODELS; CHIRAL SYMMETRY; COUPLING; FLAVOR MODEL; GLUEBALLS; GLUONS; MESON SPECTROSCOPY; MIXING; POTENTIALS; QUARK-ANTIQUARK INTERACTIONS; QUARKS; REST MASS; SCALAR MESONS
Citation Formats
Silvestre-Brac, B., Vijande, J., Fernandez, F., and Valcarce, A.. Scalar Mesons As A Mixing Of Two And Four Quark States. United States: N. p., 2006.
Web. doi:10.1063/1.2176561.
Silvestre-Brac, B., Vijande, J., Fernandez, F., & Valcarce, A.. Scalar Mesons As A Mixing Of Two And Four Quark States. United States. doi:10.1063/1.2176561.
Silvestre-Brac, B., Vijande, J., Fernandez, F., and Valcarce, A.. Sat .
"Scalar Mesons As A Mixing Of Two And Four Quark States". United States.
doi:10.1063/1.2176561.
@article{osti_20798153,
title = {Scalar Mesons As A Mixing Of Two And Four Quark States},
author = {Silvestre-Brac, B. and Vijande, J. and Fernandez, F. and Valcarce, A.},
abstractNote = {The scalar mesons are a puzzling problem in meson spectroscopy: they appear to be too numerous and with a mass often incompatible with usual quark-quark potentials. In this paper, we study the possibility to describe them as a mixing of states composed of one and two quark-antiquark pairs. A potential containing confinement, gluon exchange and boson exchange, as expected from chiral symmetry, is used in a consistent way to calculate the two and four quark states separately. Then, a coupling between these states is introduced as a constant term depending only on the flavour of the created pair. The description is largely improved. To refine the treatment, a coupling with a glueball is also considered. All the experimental resonances seem to fit correctly in this scheme.},
doi = {10.1063/1.2176561},
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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