Logo image
ϒ(nS) polarizations versus particle multiplicity in pp collisions at √s=7 TeV
Journal article   Open access   Peer reviewed

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

C Albajar, M Missiroli, D Morán, V Khachatryan, J. F Trocóniz and CMS Collaboration
Physics letters. B, Vol.761, pp.31-52
08/02/2016
DOI: 10.1016/j.physletb.2016.07.065
url
https://doi.org/10.1016/j.physletb.2016.07.065View
Published (Version of record) Open Access

Abstract

The polarizations of the ϒ(1S), ϒ(2S), and ϒ(3S) mesons are measured as a function of the charged particle multiplicity in proton–proton collisions at 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 4.9 fb−1. The results are extracted from the dimuon decay angular distributions, in two ranges of ϒ(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 ϒ(2S) and ϒ(3S) cases.
Physics Física QCD medium effects Quarkonium polarization Quarkonium production

Details

Metrics

Logo image