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Exclusive photoproduction of a heavy vector meson in QCD

D. Y. Ivanov·A. Schaefer·L. Szymanowski·G. Krasnikov
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Abstract

The process of exclusive heavy vector meson photoproduction, gamma p -> V p, is studied in the framework of QCD factorization. The mass of the produced meson, V = Upsilon or J/Psi, provides a hard scale for the process. We demonstrate, that in the heavy quark limit and at the one-loop order in perturbation theory, the amplitude factorizes in a convolution of a perturbatively calculable hard-scattering amplitude with the generalized parton densities and the nonrelativistic QCD matrix element _V. We evaluate the hard scattering amplitude at one-loop order and compare the data with theoretical predictions using an available model for generalized parton distributions.

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D. Y. Ivanov, A. Schaefer, L. Szymanowski, G. Krasnikov. 2015-06-26. Exclusive photoproduction of a heavy vector meson in QCD. https://doi.org/10.1140/epjc%2Fs2004-01712-x

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