Abstract: The ratios of the production cross sections between the excited ?(2S) and ?(3S) mesons and the ?(1S) ground state, detected via their decay into two muons, are studied as a function of the number of charged particles in the event. The data are from proton-proton collisions at ?s = 7 TeV, corresponding to an integrated luminosity of 4.8 fb-1, collected with the CMS detector at the LHC. Evidence of a decrease in these ratios as a function of the particle multiplicity is observed, more pronounced at low transverse momentum p??T. For ?(nS) mesons with p??T > 7 GeV, where most of the data were collected, the correlation with multiplicity is studied as a function of the underlying event transverse sphericity and the number of particles in a cone around the ?(nS) direction. The ratios are found to be multiplicity independent for jet-like events. The mean p??T values for the ?(nS) states as a function of particle multiplicity are also measured and found to grow more steeply as their mass increases.

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