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arXiv · hep-ph/0503193

Pentaquark Decay Width in QCD Sum Rules

M. Eidemüller·F. S. Navarra·M. Nielsen·R. Rodrigues da Silva
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Abstract

In a diquark-diquark-antiquark picture of the pentaquark we study the decay $Θ\rightarrow K^{+} n$ within the framework of QCD sum rules. After evaluation of the relevant three-point function, we extract the coupling $g_{ΘnK}$ which is directly related to the pentaquark width. Restricting the decay diagrams to those with color exchange between the meson-like and baryon-like clusters reduces the coupling constant by a factor of four. Whereas a small decay width might be possible for a positive parity pentaquark, it seems difficult to explain the measured width for a pentaquark with negative parity.

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M. Eidemüller, F. S. Navarra, M. Nielsen, R. Rodrigues da Silva. 2005-03-18. Pentaquark Decay Width in QCD Sum Rules. https://doi.org/10.1103/physrevd.72.034003

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