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.

arXiv commentv2: shortened, references added, typos corrected

References in corpus (12)

• High-Energy-Physics Event Generation with PYTHIA 6.1
• Systematic Study of High p_T Hadron Spectra in pp, pA and AA Collisions from SPS to RHIC Energies
• Dynamical Parton Distributions Revisited
• Parton intrinsic motion in inclusive particle production: unpolarized cross sections, single spin asymmetries and the Sivers effect
• High-p_T pion and kaon production in relativistic nuclear collisions
• Effects of Parton Intrinsic Transverse Momentum on Photon Production in Hard-Scattering Processes
• Transverse momentum dependence of the quark helicity distributions and the Cahn effect in double-spin asymmetry $A_{LL}$ in Semi Inclusive DIS
• Dilepton production near partonic threshold in transversely polarized proton-antiproton collisions
• Need for fully unintegrated parton densities
• Quark Initial State Interaction in Deep Inelastic Scattering and the Drell-Yan process
• Prediction for the transverse momentum distribution of Drell-Yan dileptons at GSI-PANDA
• QCD coherence effects in high energy reactions with nuclei

Cited by in corpus (5)

• Hadronic and partonic sources of direct photons in relativistic heavy-ion collisions
• Collisional processes of on-shell and off-shell heavy quarks in vacuum and in the Quark-Gluon-Plasma
• Dilepton production by dynamical quasiparticles in the strongly interacting quark gluon plasma
• Dileptons from the strongly-interacting Quark-Gluon Plasma within the Parton-Hadron-String-Dynamics (PHSD) approach
• Phenomenological model for the Drell-Yan process: Reexamined