par Chatrchyan, Serguei;Clerbaux, Barbara ;De Lentdecker, Gilles ;Marage, Pierre ;Vander Velde, Catherine ;Vanlaer, Pascal ;Gay, Arnaud ;Hreus, Tomas ;Wang, Jian ;Leonard, Alexandre ;Reis, Thomas ;Thomas, Laurent ;Dero, Vincent ;Mohammadi, Abdollah ; [et al.]
Référence Physical review letters, 110, 8, 081802
Publication Publié, 2013-02-20
Référence Physical review letters, 110, 8, 081802
Publication Publié, 2013-02-20
Article révisé par les pairs
Résumé : | The polarizations of the υ(1S), υ(2S), and υ(3S) mesons are measured in proton-proton collisions at √s=7 TeV, using a data sample of υ(nS)→μ+μ- decays collected by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb-1. The dimuon decay angular distributions are analyzed in three different polarization frames. The polarization parameters λ™, λφ, and λ, as well as the frame-invariant quantity λ, are presented as a function of the υ(nS) transverse momentum between 10 and 50 GeV, in the rapidity ranges |