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arXiv · hep-lat/0409121

Penta-Quark Anti-Decuplet in Anisotropic Lattice QCD

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

The penta-quark(5Q) Theta^+(1540) is studied in anisotropic lattice QCD with renormalized anisotropy a_s/a_t=4 for a high-precision measurement. Both the positive and the negative parity 5Q baryons 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 heavy to be identified with Theta^+(1540). In the negative parity channel, the lowest energy state is found at m_{Theta}\simeq 1.75 GeV. Although it is rather close to the empirical value, it is considered to be an NK scattering state rather than a localized resonance state.

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N. Ishii, T. Doi, H. Iida, M. Oka, F. Okiharu, H. Suganuma. 2004-09-19. Penta-Quark Anti-Decuplet in Anisotropic Lattice QCD. https://doi.org/10.1016/j.nuclphysbps.2004.11.296

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