Abstract
Bottomonia are important probes of the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. The three Upsilon states (1S, 2S, 3S) are measured separately using the Compact Muon Solenoid (CMS) experimental apparatus and were observed to disappear sequentially in PbPb collisions at 2.76 TeV. However, recent measurements in pp and pPb collisions, at 2.76 and 5.02 TeV respectively, show a surprising dependence of the excited (2S or 3S) over the ground (1S) state ratio, as a function of the global event activity. The three states are also observed to be individually more produced in events with more activity, for the three collision systems. The latest results from pp, pPb and PbPb collisions are presented in this paper. (C) 2014 CERN. Published by Elsevier B.V. All rights reserved.