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Colour-Octet Contributions to J/psi Production via Fragmentation at HERA

Bernd A. Kniehl
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Abstract

We study J/psi photoproduction via fragmentation at next-to-leading order in the QCD-improved parton model, using the nonrelativistic factorization formalism proposed by Bodwin, Braaten, and Lepage. We predict that measurements of J/psi photoproduction at DESY HERA should show a distinctive excess over the expectation based on the colour-singlet model at small values of the inelasticity variable z.

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Bernd A. Kniehl. 1997-11-24. Colour-Octet Contributions to J/psi Production via Fragmentation at HERA. https://arxiv.org/abs/hep-ph/9711443

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