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CHARM CONTENT OF A PHOTON AND $J/ψ$ PHOTOPRODUCTION AT HIGH ENERGIES

V. A. Saleev
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Abstract

A study of the $J/ψ$-meson production at large transverse momentum in high energy $γp$ collisions via the charm quark excitation in a photon is presented. Based on perturbative QCD and the nonrelativistic quark model, our calculation demonstrates that the charm content of a photon may be very important for the $J/ψ$ photoproduction at the large transverse momentum. It is shown that at HERA energies $J/ψ$ production via the subprocess $cg\to J/\si c$ dominates over the resolved photon contribution via the subprocess $gg\to J/ψg$ at $p_{\bot}>3$ GeV/c and over the direct photon-gluon fusion contribution at $p_{bot}>10$ GeV/c.

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V. A. Saleev. 1995-03-13. CHARM CONTENT OF A PHOTON AND $J/ψ$ PHOTOPRODUCTION AT HIGH ENERGIES. https://arxiv.org/abs/hep-ph/9502233

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