Khachatryan, V.Sirunyan, A. M.Tumasyan, A.Adam, W.Asilar, E.Bergauer, T.The CMS Collaboration2025-03-072025-03-0720160370-26931873-2445https://doi.org/10.1016/j.physletb.2016.07.065https://hdl.handle.net/20.500.12507/2939The polarizations of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) mesons are measured as a function of the charged particle multiplicity in proton-proton collisions at root s = 7 TeV. The measurements are performed with a dimuon data sample collected in 2011 by the CMS experiment, corresponding to an integrated luminosity of 4.9fb(-1). The results are extracted from the dimuon decay angular distributions, in two ranges of Upsilon(nS) transverse momentum (10-15 and 15-35 GeV), and in the rapidity interval |y| < 1.2. The results do not show significant changes from low-to high-multiplicity pp collisions, although large uncertainties preclude definite statements in the Upsilon(2S) and Upsilon(3S) cases. (C) 2016 The Author(s). Published by Elsevier B.V.eninfo:eu-repo/semantics/openAccessCMSPhysicsQuarkonium productionQuarkonium polarizationQCD medium effectsArticle7613152WOS:0003844699000062-s2.0-8498230718810.1016/j.physletb.2016.07.065Q1Q1