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Testing Color Evaporation in Photon-Photon Production of J/Psi at CERN LEP II

O. J. P. Eboli·E. M. Gregores·J. K. Mizukoshi
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Abstract

The DELPHI Collaboration has recently reported the measurement of J/Psi production in photon-photon collisions at LEP II. These newly available data provide an additional proof of the importance of colored c bar{c} pairs for the production of charmonium because these data can only be explained by considering resolved photon processes. We show here that the inclusion of color octet contributions to the J/Psi production in the framework of the color evaporation model is able to reproduce this data. In particular, the transverse-momentum distribution of the J/Psi mesons is well described by this model.

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O. J. P. Eboli, E. M. Gregores, J. K. Mizukoshi. 2003-08-11. Testing Color Evaporation in Photon-Photon Production of J/Psi at CERN LEP II. https://doi.org/10.1103/physrevd.68.094009

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