2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42713We 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.6 pages, 3 figures, contribution to DIS03High Energy Physics - PhenomenologyHeavy Quarkonium Production with Polarized Hadrons and Photonstext