Theoretical Modeling of J/psi Yield Modifications in Proton (Deuteron) - Nucleus Collisions at High Energy

Understand

Understanding the detailed production and hadronization mechanisms for heavy quarkonia and their modification in a nuclear environment presents one of the major challenges in QCD.

• Calculations including nuclear-modified parton distribution functions (nPDFs) and fitting of break-up cross sections (sigma_breakup) as parameters have been successful at describing many features of J/psi modification in proton(deuteron)-nucleus collisions.
• In this paper, we extend these calculations to explore different geometric dependencies of the modification and confront them with new experimental results from the PHENIX experiment.
• We find that no combination of nPDFs and sigma_breakup, regardless of the nPDF parameter set and the assumed geometric dependence, can simultaneously describe the entire rapidity and centrality dependence of J/psi modifications in d+Au collisions at sqrt(s_NN) = 200 GeV.