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تسجيل مستخدم جديدTesting Color Evaporation in Photon-Photon Production of J/Psi at CERN LEP II
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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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