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arXiv · hep-lat/0410025

Lattice QCD Study of the Pentaquark Baryons

T. T. Takahashi·T. Umeda·T. Onogi·T. Kunihiro
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Abstract

We study the spin $\frac12$ hadronic state in quenched lattice QCD to search for a possible $S=+1$ pentaquark resonance. Simulations are carried out on $8^3\times 24$, $10^3\times 24$, $12^3\times 24$ and $16^3\times 24$ lattices at $β$=5.7 at the quenched level with the standard plaquette gauge action and Wilson quark action. We adopt two independent operators with I=0 and $J^P=\frac12$ to construct a $2\times 2$ correlation matrix. After the diagonalization of the correlation matrix, we successfully obtain the energies of the ground-state and the 1st excited-state in this channel. The volume dependence of the energies suggests the existence of a possible resonance state slightly above the NK threshold in I=0 and $J^P=\frac12^-$ channel.

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T. T. Takahashi, T. Umeda, T. Onogi, T. Kunihiro. 2004-10-25. Lattice QCD Study of the Pentaquark Baryons. https://doi.org/10.1142/9789812701855_0046

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