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The narrow pentaquark

Dmitri Diakonov
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Abstract

The experimental status of the pentaquark searches is briefly reviewed. Recent null results by the CLAS collaboration are commented, and new strong evidence of a very narrow Theta+ resonance by the DIANA collaboration is presented. On the theory side, I revisit the argument against the existence of the pentaquark -- that of Callan and Klebanov -- and show that actually a strong resonance is predicted in that approach, however its width is grossly overestimated. A recent calculation gives 2 MeV for the pentaquark width, and this number is probably still an upper bound.

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Dmitri Diakonov. 2006-10-13. The narrow pentaquark. https://doi.org/10.1063/1.2714388

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