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arXiv · hep-ph/0607305

Next-to-leading order vs. quark off-shellness and intrinsic k_T in the Drell-Yan process

Abstract

We calculate the effects of next-to-leading order perturbative QCD as well as of the quark transverse motion and off-shellness on the Drell-Yan process cross section. By studying the s->infinity behaviour of the cross section in these approaches, we find that the effects of quark off-shellness and intrinsic-k_T parametrize those of higher twists. In particular, the off-shellness of partons generates part of the K-factor type corrections to the leading order cross section. Higher twist contributions to the p_T-spectrum of the Drell-Yan pairs are found to be large for presently accessible energies. The evolution of quark off-shellness distribution with the hard scale is also studied.

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BibTeXRIS

O. Linnyk, S. Leupold, U. Mosel. 2006-11-20. Next-to-leading order vs. quark off-shellness and intrinsic k_T in the Drell-Yan process. https://doi.org/10.1103/physrevd.75.014016

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