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arXiv · 1012.3022

Inclusive J/Psi photoproduction and polarization at HERA in the kt-factorization approach

S. P. Baranov·A. V. Lipatov·N. P. Zotov
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Abstract

We investigate the inclusive photoproduction of J/Psi mesons at HERA within the framework of the kt-factorization QCD approach. Our consideration is based on the color singlet model supplemented with the relevant off-shell matrix elements and the CCFM and KMR unintegrated gluon densities in a proton and in a photon. Both the direct and resolved photon contributions are taken into account. Our predictions are compared with the recent experimental data taken by the H1 and ZEUS collaborations. Special attention is put on the J/Psi polarization parameters lambda and nu which are sensitive to the production dynamics.

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S. P. Baranov, A. V. Lipatov, N. P. Zotov. 2010-12-14. Inclusive J/Psi photoproduction and polarization at HERA in the kt-factorization approach. https://doi.org/10.1140/epjc%2Fs10052-011-1631-4

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