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J/ψProduction in Direct and Resolved Photon Collisions

Michael Klasen
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Abstract

The production of J/Psi mesons in photon photon collisions allows for a test of factorization in color-octet processes as predicted by NRQCD and observed at the Tevatron. We calculate the cross sections for J/Psi production with direct and resolved photons, including also the feed-down from chi_{cJ} and Psi' decays. Our NRQCD predictions are nicely confirmed by recent data from the DELPHI collaboration at CERN LEP2.

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Michael Klasen. 2003-04-29. J/ψProduction in Direct and Resolved Photon Collisions. https://arxiv.org/abs/hep-ph/0304271

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