Measurement of the prompt J/ψ and ψ(2S) polarizations in pp collisions at √s=7 TeV
Abstract
The polarizations of prompt J/ψ and ψ(2S) mesons are measured in proton-proton collisions at s=7 TeV, using a dimuon data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.9 fb-1. The prompt J/ψ and ψ(2S) polarization parameters λθ{symbol}, λφ, and λθ{symbol}φ, as well as the frame-invariant quantity λ~, are measured from the dimuon decay angular distributions in three different polarization frames. The J/ψ results are obtained in the transverse momentum range 14<pT<70 GeV, in the rapidity intervals |y|<0.6 and 0.6<|y|<1.2. The corresponding ψ(2S) results cover 14<pT<50 GeV and include a third rapidity bin, 1.2<|y|<1.5. No evidence of large polarizations is seen in these kinematic regions, which extend much beyond those previously explored. Mehr anzeigen
Persistenter Link
https://doi.org/10.3929/ethz-b-000075097Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
Physics Letters BBand
Seiten / Artikelnummer
Verlag
ElsevierThema
CMS; Physics; Quarkonium production; Quarkonium polarizationOrganisationseinheit
03381 - Pauss, Felicitas (emeritus)
03593 - Dissertori, Günther / Dissertori, Günther
03904 - Wallny, Rainer / Wallny, Rainer
08803 - Grab, Christoph (Tit.Prof.)