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arXiv · hep-ph/0309271

Penta-quark baryon from the QCD Sum Rule

Jun Sugiyama·Takumi Doi·Makoto Oka
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Abstract

Exotic penta-quark baryon with strangeness +1, Θ^+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J=1/2 and I=0. It is found that the standard values of the QCD condensates predict a negative parity Θ^+ of mass \simeq 1.5 GeV, while no positive parity state is found. We stress the roles of chiral-odd condensates in determining the parity and mass of Θ^+.

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Jun Sugiyama, Takumi Doi, Makoto Oka. 2003-12-09. Penta-quark baryon from the QCD Sum Rule. https://doi.org/10.1016/j.physletb.2003.12.018

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