Prompt and non-prompt J/psi production in pp collisions at root s=7 TeV


Khachatryan V., Sirunyan A. M. , Tumasyan A., Adam W., Bergauer T., Dragicevic M., ...More

EUROPEAN PHYSICAL JOURNAL C, vol.71, no.3, 2011 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 71 Issue: 3
  • Publication Date: 2011
  • Doi Number: 10.1140/epjc/s10052-011-1575-8
  • Title of Journal : EUROPEAN PHYSICAL JOURNAL C

Abstract

The production of J/psi mesons is studied in pp collisions at root s = 7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 nb(-1). The J/psi differential cross section is determined, as a function of the J/psi transverse momentum, in three rapidity ranges. A fit to the decay length distribution is used to separate the prompt from the non-prompt (b hadron to J/psi) component. Integrated over J/psi transverse momentum from 6.5 to 30 GeV/c and over rapidity in the range vertical bar y vertical bar < 2.4, the measured cross sections, times the dimuon decay branching fraction, are 70.9 +/- 2.1(stat.) +/- 3.0(syst.) +/- 7.8(luminosity) nb for prompt J/psi mesons assuming unpolarized production and 26.0 +/- 1.4(stat.) +/- 1.6(syst.) +/- 2.9(luminosity) nb for J/psi mesons from b-hadron decays.