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Charmonium production in polarized high-energy collisions

M. Klasen·B. A. Kniehl·L. Mihaila·M. Steinhauser
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Abstract

We investigate the inclusive production of prompt J/psi 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^- and gamma gamma modes of 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/psi inclusive production taken by the PHENIX Collaboration in unpolarized proton-proton collisions at RHIC tends to favor the NRQCD factorization hypothesis, while it significantly overshoots the theoretical prediction of the color-singlet model at large values of transverse momentum.

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M. Klasen, B. A. Kniehl, L. Mihaila, M. Steinhauser. 2003-11-24. Charmonium production in polarized high-energy collisions. https://doi.org/10.1103/physrevd.68.034017

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