A1 Journal article (refereed), original research

ϒ(nS)polarizations versus particle multiplicity in pp collisions at √s=7TeV

Open Access publication

Publication Details

Authors: Khachatryan V., Sirunyan A.M., Tumasyan A., Adam W., Asilar E., Bergauer T., Brandstetter J., Brondolin E., Dragicevic M., Erö J., Fabjan C., Flechl M., Friedl M., Frühwirth R., Ghete V.M., Hartl C., Hörmann N., Talvitie J, Tuuva Tuure, The CMS Collaboration

Publication year: 2016

Language: English

Related journal or series: Physics Letters B

Volume number: 761

Start page: 31

End page: 52

JUFO level of this publication: 2

Open Access: Open Access publication


The polarizations of the ϒ(1S)ϒ(1S), ϒ(2S)ϒ(2S), and ϒ(3S)ϒ(3S) mesons are measured as a function of the charged particle multiplicity in proton-proton collisions at s=7TeV. The measurements are performed with a dimuon data sample collected in 2011 by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb-1. The results are extracted from the dimuon decay angular distributions, in two ranges of ϒ(nS)ϒ(nS) transverse momentum (10-15 and 15-35 GeV), and in the rapidity interval |y|<1.2|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 ϒ(2S)ϒ(2S) and ϒ(3S)ϒ(3S) cases.

Last updated on 2018-19-10 at 08:49