Measurement of J/ψ polarization in pp collisions at √s = 7 TeV

Abstract

An angular analysis of the decay J/ψ → μ + μ − is performed to measure the polarization of prompt J/ψ mesons produced in pp collisions at √s = 7 TeV. The dataset corresponds to an integrated luminosity of 0.37 fb −1 collected with the LHCb detector. The measurement is presented as a function of transverse momentum, p T, and rapidity, y, of the J/ψ meson, in the kinematic region 2 < T < 15 GeV/c and 2.0 < y < 4.5.