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arXiv · hep-lat/0504015

Spin 3/2 Pentaquark Resonance Signature in Lattice QCD

B. G. Lasscock·D. B. Leinweber·W. Melnitchouk·A. W. Thomas·A. G. Williams·R. D. Young·J. M. Zanotti
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Abstract

The possible discovery of the Theta+ pentaquark has motivated a number of studies of its nature using lattice QCD. While all the analyses thus far have focussed on spin-1/2 states, here we report the results of the first exploratory study in quenched lattice QCD of pentaquarks with spin 3/2. For the spin-3/2 interpolating field we use a product of the standard N and K* operators. We do not find any evidence for the standard lattice resonance signature of attraction (i.e., binding at quark masses near the physical regime) in the J^P = 3/2- channel. Some evidence of binding is inferred in the isoscalar 3/2+ channel at several quark masses, in accord with the standard lattice resonance signature. This suggests that this is a good candidate for the further study of pentaquarks on the lattice.

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B. G. Lasscock, D. B. Leinweber, W. Melnitchouk, A. W. Thomas, A. G. Williams, R. D. Young, J. M. Zanotti. 2005-10-07. Spin 3/2 Pentaquark Resonance Signature in Lattice QCD. https://doi.org/10.1103/physrevd.72.074507

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