Measurement of the prompt J/psi and psi(2S) polarizations in pp collisions at sqrt(s) = 7 TeV - IN2P3 - Institut national de physique nucléaire et de physique des particules Access content directly
Journal Articles Physics Letters B Year : 2013

Measurement of the prompt J/psi and psi(2S) polarizations in pp collisions at sqrt(s) = 7 TeV

S. Chatrchyan
  • Function : Author
Pierre Busson
R. Granier de Cassagnac
C. Mironov
P. Paganini
J.-L. Agram
C. Collard
E. Conte
P. van Hove
D. Contardo
M. Gouzevitch
M. Lethuillier
V. Sordini
P. Verdier
S. Viret

Abstract

The polarizations of prompt J/psi and psi(2S) mesons are measured in proton-proton collisions at sqrt(s) = 7 TeV, using a dimuon data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.9 inverse femtobarns. The prompt J/psi and psi(2S) polarization parameters lambda[theta], lambda[phi], and lambda[theta,phi], as well as the frame-invariant quantity lambda, are measured from the dimuon decay angular distributions in three different polarization frames. The J/spi results are obtained in the transverse momentum range 14 < pt < 70 GeV, in the rapidity intervals abs(y) < 0.6 and 0.6 < abs(y) < 1.2. The corresponding psi(2S) results cover 14 < pt < 50 GeV and include a third rapidity bin, 1.2 < abs(y) < 1.5. No evidence of large transverse or longitudinal polarizations is seen in these kinematic regions, which extend much beyond those previously explored.

Dates and versions

in2p3-00847615 , version 1 (24-07-2013)

Identifiers

Cite

S. Chatrchyan, M. Besançon, F. Couderc, M. Dejardin, D. Denegri, et al.. Measurement of the prompt J/psi and psi(2S) polarizations in pp collisions at sqrt(s) = 7 TeV. Physics Letters B, 2013, 727, pp.381-402. ⟨10.1016/j.physletb.2013.10.055⟩. ⟨in2p3-00847615⟩
79 View
0 Download

Altmetric

Share

Gmail Facebook X LinkedIn More