Y(nS) polarizations versus particle multiplicity in pp collisions at sqrt(s) = 7 TeV

Abstract

The polarizations of the Y(1S), Y(2S), and Y(3S) mesons are measured as a function of the charged particle multiplicity in proton-proton collisions at sqrt(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 inverse femtobarns. The results are extracted from the dimuon decay angular distributions, in two ranges of Y(nS) transverse momentum (10-15 and 15-35 GeV), and in the rapidity interval abs(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 Y(2S) and Y(3S) cases.

Replaced with published version. Added the journal reference and DOI. All figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIN-15-003/index.html

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Cited by in corpus (9)

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• First measurement of quarkonium polarization in nuclear collisions at the LHC
• Measurement of prompt $\psi$(2S) production cross sections in proton-lead and proton-proton collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=$ 5.02 TeV
• Investigation into the event-activity dependence of ${\rm Y}$(nS) relative production in proton-proton collisions at $\sqrt{s}=$ 7 TeV
• Observation of the ${\rm Y}$(3S) meson and suppression of ${\rm Y}$ states in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Shedding Light on Hadronization by Quarkonium Energy Correlator
• $J/\psi$ and $\psi$(2S) polarization in proton-proton collisions at energies available at the CERN Large Hadron Collider using PYTHIA8