Forward $J/\psi$ production at high energy: centrality dependence and mean transverse momentum

Understand

Forward rapidity $J/\psi$ meson production in proton-nucleus collisions can be an important constraint of descriptions of the small-$x$ nuclear wavefunction.

• In an earlier work we studied this process using a dipole cross section satisfying the Balitsky-Kovchegov equation, fit to HERA inclusive data and consistently extrapolated to the nuclear case using a standard Woods-Saxon distribution.
• In this paper we present further calculations of these cross sections, studying the mean transverse momentum of the meson and the dependence on collision centrality.
• We also extend the calculation to backward rapidities using nuclear parton distribution functions.