ϒ(nS) polarizations versus particle multiplicity in pp collisions at √s=8TeV

Abstract

The polarizations of the , , and mesons are measured as a function of the charged particle multiplicity in proton–proton collisions at . 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 transverse momentum (10–15 and 15–35 GeV), and in the rapidity interval . The results do not show significant changes from low- to high-multiplicity pp collisions, although large uncertainties preclude definite statements in the and cases.