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Heavy Quarkonium Production with Polarized Hadrons and Photons

M. Klasen·B. A. Kniehl
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Abstract

We investigate the inclusive production of prompt J/psi mesons in polarized hadron-hadron and photon-hadron collisions in the factorization formalism of NRQCD. Numerical results are presented for BNL RHIC-Spin and the approved SLAC fixed-target experiment E161 to assess the feasibility to access the spin-dependent parton distributions in the polarized proton and photon. We point out that data on J/psi 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 CSM.

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M. Klasen, B. A. Kniehl. 2003-07-31. Heavy Quarkonium Production with Polarized Hadrons and Photons. https://arxiv.org/abs/hep-ph/0307384

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