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Title: Color SU(3) symmetry, confinement, stability, clustering and quark mass dependence in the q{sup 4}q system

Abstract

We examine the color SU(3) dynamics of q{sup 4}q system, i.e. of the pentaquark. First we study this system in the model with two-body interaction proportional to the color charges. We construct the potential matrix and show, (1) Confinement: the color singlet qq potential energy rises infinitely with the separation distance, (2) Stability: All colorless states' energies are bounded from below (3) Color singlet clustering: the pentaquark color-singlet state Hamiltonian turns into a sum of a three-quark (baryon) and a quark-antiquark (meson) cluster Hamiltonian, in the limit of asymptotically large separations. We evaluate the four excitation eigenfrequencies of pentaquarks in the harmonic oscillator two-body confining potential and the ground states' dependence on the quark-antiquark mass ratio. We show that the pentaquark is unlikely to bind even with a top antiquark, in contrast to tetraquarks.

Authors:
 [1]
  1. Vinca Institute of Nuclear Sciences, lab 010, P.O. Box 522, 11001 Belgrade (Serbia and Montenegro)
Publication Date:
OSTI Identifier:
20776656
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.73.034014; (c) 2006 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; BARYONS; COLOR MODEL; DISTANCE; EIGENFREQUENCY; EXCITATION; GROUND STATES; HAMILTONIANS; HARMONIC OSCILLATORS; MESONS; PARTICLE INTERACTIONS; POTENTIAL ENERGY; POTENTIALS; QUARKS; REST MASS; STABILITY; SU-3 GROUPS; TWO-BODY PROBLEM

Citation Formats

Dmitrasinovic, V. Color SU(3) symmetry, confinement, stability, clustering and quark mass dependence in the q{sup 4}q system. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.034014.
Dmitrasinovic, V. Color SU(3) symmetry, confinement, stability, clustering and quark mass dependence in the q{sup 4}q system. United States. doi:10.1103/PhysRevD.73.034014.
Dmitrasinovic, V. Wed . "Color SU(3) symmetry, confinement, stability, clustering and quark mass dependence in the q{sup 4}q system". United States. doi:10.1103/PhysRevD.73.034014.
@article{osti_20776656,
title = {Color SU(3) symmetry, confinement, stability, clustering and quark mass dependence in the q{sup 4}q system},
author = {Dmitrasinovic, V.},
abstractNote = {We examine the color SU(3) dynamics of q{sup 4}q system, i.e. of the pentaquark. First we study this system in the model with two-body interaction proportional to the color charges. We construct the potential matrix and show, (1) Confinement: the color singlet qq potential energy rises infinitely with the separation distance, (2) Stability: All colorless states' energies are bounded from below (3) Color singlet clustering: the pentaquark color-singlet state Hamiltonian turns into a sum of a three-quark (baryon) and a quark-antiquark (meson) cluster Hamiltonian, in the limit of asymptotically large separations. We evaluate the four excitation eigenfrequencies of pentaquarks in the harmonic oscillator two-body confining potential and the ground states' dependence on the quark-antiquark mass ratio. We show that the pentaquark is unlikely to bind even with a top antiquark, in contrast to tetraquarks.},
doi = {10.1103/PhysRevD.73.034014},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 73,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2006},
month = {Wed Feb 01 00:00:00 EST 2006}
}
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