  We suggest that gluon-induced dissociation and screening of the Y(nS) states
explain the suppression of the Y(2S+3S) states relative to the Y(1S) ground
state that has been observed by CMS in PbPb collisions at sqrt(s_NN)= 2.76 TeV
at the CERN LHC. The minimum-bias gluodissociation cross sections of the 1S-3S
states are calculated using a screened Cornell potential and a thermal gluon
distribution. The 3S state dissolves due to screening before sizeable
gluodissociation occurs, but for the 2S and 1S states there is an interplay
between screening, gluodissociation, and feed-down from the chi_b(2P) and
chi_b(1P) states. Based on a schematic approach, we find that the calculated
suppression of the Y(2S) and Y(3S) states relative to Y(1S) is consistent with
the CMS result, but allows for additional suppression mechanisms. The Y(1S)
suppression through gluodissociation is, however, in good agreement with the
CMS data.
