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arXiv · hep-lat/0501022

Penta-quark in Anisotropic Lattice QCD

N. Ishii·T. Doi·H. Iida·M. Oka·F. Okiharu·H. Suganuma
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Abstract

Penta-quark (5Q) baryons are studied using anisotropic lattice QCD for high-precision measurement of temporal correlators. A non-NK-type interpolating field is employed to study the 5Q states with J^P=1/2^{\pm} and I=0. In J^P=1/2^+ channel, the lowest-lying state is found at m_{5Q} \simeq 2.25 GeV, which is too massive to be identified as the Theta^+(1540). In J^P=1/2^- channel, the lowest-lying state is found at m_{5Q} \simeq 1.75 GeV. To distinguish a compact 5Q resonance state from an NK scattering state, a new method with ``hybrid boundary condition (HBC)'' is proposed. As a result of the HBC analysis, the observed state in the negative-parity channel turns out to be an $NK$ scattering state.

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N. Ishii, T. Doi, H. Iida, M. Oka, F. Okiharu, H. Suganuma. 2005-01-26. Penta-quark in Anisotropic Lattice QCD. https://doi.org/10.1016/j.nuclphysa.2005.03.057

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