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Colour Octet Contribution in Exclusive Charmonium Decay into Baryon-Antibaryon

P. Kroll·S. M. H. Wong
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Abstract

It is argued that colour octet contribution in exclusive charmonium decays is very important even though the same infrared divergence found in P-wave colour singlet inclusive decay is absent. This comes about because of the suppression at the level of the wavefunction of P-wave quarkonia. Using the modified hard scattering approach of Brodsky, Lepage, Botts, Li and Sterman, we use charmonium decay into baryon-antibaryon pair as an example and show that the colour singlet contribution alone is clearly insufficient to explain the experimental decay widths.

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P. Kroll, S. M. H. Wong. 1997-10-24. Colour Octet Contribution in Exclusive Charmonium Decay into Baryon-Antibaryon. https://arxiv.org/abs/hep-ph/9710464

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