2003/06/30 by M. Klasen, Michael Klasen, Bernd A. Kniehl +4 · 1 citation
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.68.034017
published as Phys.Rev. D68 (2003) 034017 · 34 pages (Latex), 5 figures (Postscript), typos fixed, matches journal version
openalex publication_date 2003/08/27 · arxiv created 2003/11/24 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We investigate the inclusive production of prompt J/\ensuremathψ mesons in polarized hadron-hadron, photon-hadron, and photon-photon collisions in the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD) providing all contributing partonic cross sections in analytic form. In the case of photoproduction, we also include the resolved-photon contributions. We present numerical results appropriate for BNL RHIC-Spin, the approved SLAC fixed-target experiment E161, and the e+e^\ensuremath- and \ensuremathγ\ensuremathγ modes of DESY TESLA. Specifically, we assess the feasibility to access the spin-dependent parton distributions in the polarized proton and photon. We also point out that preliminary data on J/\ensuremathψ inclusive production taken by the PHENIX Collaboration in unpolarized proton-proton collisions at RHIC tend to favor the NRQCD factorization hypothesis, while they significantly overshoot the theoretical prediction of the color-singlet model at large values of transverse momentum.