Centrality, rapidity, and transverse-momentum dependence of gluon shadowing and antishadowing on $J/\psi$ production in $d$Au collisions at $\sqrt{s}$=200 GeV

Abstract

We have carried out a wide study of shadowing and antishadowing effects on \jpsi\ production in \dAu\ collisions at $\sqrt{s_{NN}}=200$ GeV. We have studied the effects of three different gluon nPDF sets, using the exact kinematics for a $2\to 2$ process, namely $g+g\to J/\psi +g$ as expected from LO pQCD. We have computed the rapidity dependence of \RCP\ and $R_{d\mathrm{Au}}$ for the different centrality classes of the PHENIX data. For mid rapidities, we have also computed the transverse-momentum dependence of the nuclear modification factor, which cannot be predicted with the usual $2\to 1$ simplified kinematics. All these observables have been compared to the PHENIX data in \dAu\ collisions.

Comments: 10 pages, 11 figures, talk given by N. Matagne at the conference "thirty years of hadronic physics", Spa, Belgium, April 6-8, 2011, to appear in Few Body Systems