Abstract :
differential cross section. I also emphasise the very good agreement between the parameter-free predictions of the Colour-Singlet Model (CSM) and the first LHC data, especially in the region of low transverse momenta, which is the most relevant one for heavy-ion studies. I also show that the CSM predicts ϒ cross-section ratios in agreement with the most recent LHC data. I then briefly discuss the nuclear-matter effects on ϒ production at RHIC and the LHC in p(d)A collisions and, by extension, in AA collisions. I argue that a) the ϒ break-up probability can be neglected, at RHIC and the LHC, b) gluon shadowing –although non-negligible– is not strong enough to describe forward RHIC data, c) backward RHIC data hints at a gluon EMC effect, possibly stronger than the quark one. Outlooks for the LHC pPb run are also presented.
Keywords :
proton–proton collisions , ? production , Heavy-ion collisions , cold nuclear matter effects