ϒsuppression in PbPb collisions at energies available at the CERN Large Hadron Collider

We suggest that the combined effect of screening, gluon-induced dissociation, collisional damping, and reduced feed-down explains most of the sequential suppression of Υ(nS) states that has been observed in PbPb relative to $pp$ collisions at √sNN=2.76 TeV. The suppression is thus a clear, albeit indirect, indication of the presence of a quark-gluon plasma. The Υ(1S) ground state suppression is essentially due to reduced feed-down, collisional damping, and gluon-induced dissociation, whereas screening prevails for the suppression of the excited states.