Speaker
Bertrand Ducloue
(University of Jyvaskyla)
Description
Inclusive production of J/psi mesons, especially at forward rapidities, is an important probe of small-x gluons in protons and nuclei. In this work we re-evaluate the production cross sections in the Color Glass Condensate framework, where the process is described by a large x gluon from the probe splitting into a quark pair and eikonally interacting with the target proton or nucleus. Using a standard collinear gluon distribution for the probe and an up to date dipole cross section fitted to HERA data to describe the target we achieve a rather good description of the cross section in proton-proton collisions, although with a rather large normalization uncertainty. More importantly, we show that generalizing the dipole cross section to nuclei in the Glauber approach results in a nuclear suppression of J/psi production that is much closer to the experimental data than claimed in previous literature.
Authors
Bertrand Ducloue
(University of Jyvaskyla)
Heikki Mäntysaari
(University of Jyväskylä)
Tuomas Lappi
(University of Jyvaskyla)
