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A QCD sum rule analysis of the pentaquark

Hee-Jung Lee·N. I. Kochelev·V. Vento
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Abstract

We perform a QCD sum rule calculation to determine the mass and the parity of the lowest lying pentaquark state. We include operators up to dimension $d=13$ in the OPE and the direct instanton contributions. We find evidence for a positive parity state. The contribution from operators of dimension $d>5$ is instrumental in determining the parity of the state and achieving the convergence of the sum rule.

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Hee-Jung Lee, N. I. Kochelev, V. Vento. 2005-12-30. A QCD sum rule analysis of the pentaquark. https://doi.org/10.1103/physrevd.73.014010

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