HEAVY QUARKONIUM PRODUCTION WITH POLARIZED HADRONS AND PHOTONS∗ MICHAEL KLASEN and BERND A. KNIEHL
نویسندگان
چکیده
We investigate the inclusive production of prompt J/ψ mesons in polarized hadron-hadron and photon-hadron collisions in the factorization formalism of NRQCD. Numerical results are presented for BNL RHICSpin 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/ψ 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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