Tumasyan, A.Adam, W.Andrejkovic, J. W.Bergauer, ThomasChatterjee, S.Damanakis, KonstantinosDragicevic, M.2024-10-312024-10-3120240031-90071079-711410.1103/PhysRevLett.133.022302https://doi.org/10.1103/PhysRevLett.133.022302https://hdl.handle.net/11501/1547The production of Upsilon(2S) and Upsilon(3S) mesons in lead-lead (Pb-Pb) and proton-proton (pp) collisions is studied in their dimuon decay channel using the CMS detector at the LHC. The Upsilon(3S) meson is observed for the first time in Pb-Pb collisions, with a significance above 5 standard deviations. The ratios of yields measured in Pb-Pb and pp collisions are reported for both the Upsilon(2S) and Upsilon(3S) mesons, as functions of transverse momentum and Pb-Pb collision centrality. These ratios, when appropriately scaled, are significantly less than unity, indicating a suppression of Upsilon yields in Pb-Pb collisions. This suppression increases from peripheral to central Pb-Pb collisions. Furthermore, the suppression is stronger for Upsilon(3S) mesons compared to Upsilon(2S) mesons, extending the pattern of sequential suppression of quarkonium states in nuclear collisions previously seen for the J/psi, psi(2S), Upsilon(1S), and Upsilon(2S) mesons.eninfo:eu-repo/semantics/openAccess√sNN=5.02 TeVPb-Pb CollisionsMeson and SuppressionArticle239073941133WOS:001290703500001Q1