Title Observation of sequential $\Upsilon$ suppression in PbPb collisions Author Chatrchyan, S. Khachatryan, V. Sirunyan, A. M. Bansal, S. Cornelis, T. de Wolf, E.A. Janssen, X. Luyckx, S. Mucibello, L. Roland, B. Rougny, R. Selvaggi, M. van Haevermaet, H. Van Mechelen, P. Van Remortel, N. Van Spilbeeck, A. et al. Faculty/Department Faculty of Sciences. Physics Publication type article Publication 2012 New York, N.Y. , 2012 Subject Physics Source (journal) Physical review letters. - New York, N.Y. Volume/pages 109(2012) :22 , p. 1-15 ISSN 0031-9007 Article Reference 222301 Carrier E-only publicatie Target language English (eng) Full text (Publishers DOI) Affiliation University of Antwerp Abstract The suppression of the individual gamma (nS) states in PbPb collisions with respect to their yields in pp data has been measured. The PbPb and pp data sets used in the analysis correspond to integrated luminosities of 150 mu b(-1) and 230 nb(-1), respectively, collected in 2011 by the CMS experiment at the LHC, at a center-of-mass energy per nucleon pair of 2.76 TeV. The gamma (nS) yields are measured from the dimuon invariant mass spectra. The suppression of the gamma (nS) yields in PbPb relative to the yields in pp, scaled by the number of nucleon-nucleon collisions, R-AA, is measured as a function of the collision centrality. Integrated over centrality, the R-AA values are 0.56 +/- 0.08(stat) +/- 0.07(syst), 0.12 +/- 0.04(stat) +/- 0.02(syst), and lower than 0.10 (at 95% confidence level), for the gamma (1S), gamma (2S), and gamma (3S) states, respectively. The results demonstrate the sequential suppression of the gamma (nS) states in PbPb collisions at LHC energies. Full text (open access) https://repository.uantwerpen.be/docman/irua/2a6f12/3555.pdf E-info http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000311552100002&DestLinkType=RelatedRecords&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000311552100002&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000311552100002&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 Handle