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arXiv · 1702.02097

QCD leading order study of the $J/ψ$ leptoproduction at HERA within the nonrelativistic QCD framework

Zhan Sun·Hong-Fei Zhang
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Abstract

As indicated in our previous paper (Phys.Rev.D96.034002), the existing literatures studying the $J/ψ$ production in deeply inelastic scattering (DIS) in collinear factorization are on the basis of a formalism that will lead to wrong results when the ranges of the transverse momentum or the rapidity of the $J/ψ$ in the laboratory frame do not cover all values possible for them. In this paper, we present the renewed results for the $J/ψ$ production in DIS at HERA within the nonrelativistic QCD framework at QCD leading order (LO). Three different sets of the long-distance matrix elements are employed for comparison. The predictions via the colour-singlet (CS) model at QCD LO are generally below the experimental data especially in the regions where perturbation theory are expected to work well, while the colour-octet contributions are of the same order of magnitude as the CS ones, however, in general make the agreement between theory and experiment better.

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Zhan Sun, Hong-Fei Zhang. 2017-11-05. QCD leading order study of the $J/ψ$ leptoproduction at HERA within the nonrelativistic QCD framework. https://doi.org/10.1140/epjc%2Fs10052-017-5323-6

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