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arXiv · hep-ph/0407305

Mass spectrum of the J^P=1/2^- and 3/2^- pentaquark antidecuplets in the perturbative chiral quark model

Abstract

We study the recently discovered Theta^+ baryon in the context of the perturbative chiral quark model. The basic configuration of the Theta^+ is set up as a pentaquark bound state, where the single particle wave functions are the ground state solutions of a confining potential. We classify the resulting pentaquark multiplets as the J^P=1/2^- and 3/2^- flavor SU(3) antidecuplet. The full mass spectrum of the multiplets is determined by including meson and gluon cloud contributions inducing flavor SU(3) breaking. Mainly due to the semi-perturbative gluon effects the resulting 3/2^- antidecuplet is about 185 MeV heavier than the 1/2^- one. We assign the observed Theta^+ baryon as a member of the 1/2^- antidecuplet and discuss in particular the relation to the recent experimental signal for a Xi^{--} baryon.

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BibTeXRIS

T. Inoue, V. E. Lyubovitskij, Th. Gutsche, Amand Faessler. 2005-11-25. Mass spectrum of the J^P=1/2^- and 3/2^- pentaquark antidecuplets in the perturbative chiral quark model. https://doi.org/10.1142/s0218301305003752

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