  The ratio between the prompt psi(2S) and J/psi yields, reconstructed via
their decays into muon pairs, is measured in PbPb and pp collisions at
sqrt(s[NN]) = 2.76 TeV. The analysis is based on PbPb and pp data samples
collected by CMS at the LHC, corresponding to integrated luminosities of 150
inverse microbarns and 5.4 inverse picobarns, respectively. The double ratio of
measured yields, (N[psi(2S)]/N[J/psi])[PbPb] / (N[psi(2S)]/ N[J/psi])[pp], is
computed in three PbPb collision centrality bins and two kinematic ranges: one
at midrapidity, abs(y) < 1.6, covering the transverse momentum range 6.5 < pt <
30 GeV/c, and the other at forward rapidity, 1.6 < abs(y) < 2.4, extending to
lower pt values, 3 < pt < 30 GeV/c. The centrality-integrated double ratio
changes from 0.45 +/- 0.13 (stat) +/- 0.07 (syst) in the first range to 1.67
+/- 0.34 (stat) +/- 0.27 (syst) in the second. This difference is most
pronounced in the most central collisions.
