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Anisotropic Lattice QCD Studies of Penta-quark Anti-decuplet

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

Anti-decuplet penta-quark baryon is studied with the quenched anisotropic lattice QCD for accurate measurement of the correlator. Both the positive and negative parity states are studied using a non-NK type interpolating field with I=0 and J=1/2. After the chiral extrapolation, the lowest positive parity state is found at m_{Theta} \simeq 2.25 GeV, which is too massive to be identified with the experimentally observed Theta^+(1540). The lowest negative parity state is found at m_{Theta}\simeq 1.75 GeV, which is rather close to the empirical value. To confirm that this state is a compact 5Q resonance, a new method with ``hybrid boundary condition (HBC)'' is proposed. The HBC analysis shows that the observed state in the negative parity channel is an NK scattering state.

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N. Ishii, T. Doi, H. Iida, M. Oka, F. Okiharu, H. Suganuma. 2004-10-15. Anisotropic Lattice QCD Studies of Penta-quark Anti-decuplet. https://doi.org/10.1142/9789812701855_0045

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