Measurement of the relative prompt production rate of chi(c2) and chi(c1) in pp collisions at root s=7 TeV


Chatrchyan S., Khachatryan V., Sirunyan A. M. , Tumasyan A., Adam W., Aguilo E., ...More

EUROPEAN PHYSICAL JOURNAL C, vol.72, no.12, 2012 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 72 Issue: 12
  • Publication Date: 2012
  • Doi Number: 10.1140/epjc/s10052-012-2251-3
  • Title of Journal : EUROPEAN PHYSICAL JOURNAL C

Abstract

Ameasurement is presented of the relative prompt production rate of chi(c2) and chi(c1) with 4.6 fb(-1) of data collected by the CMS experiment at the LHC in pp collisions at root s = 7 TeV. The two states are measured via their radiative decays chi(c) -> J/psi + gamma, with the photon converting into an e(+)e(-) pair for J/psi rapidity \y(J/psi)\ < 1.0 and photon transverse momentum p(T)(gamma) > 0.5 GeV/c. The measurement is given for six intervals of p(T)(J/psi) between 7 and 25 GeV/c. The results are compared to theoretical predictions.