Measurement of BB̄ angular correlations based on secondary vertex reconstruction at √s = 7 TeV


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

Journal of High Energy Physics, vol.2011, no.3, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 2011 Issue: 3
  • Publication Date: 2011
  • Doi Number: 10.1007/jhep03(2011)136
  • Journal Name: Journal of High Energy Physics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Hadron-hadron scattering
  • Yıldız Technical University Affiliated: No

Abstract

A measurement of the angular correlations between beauty and anti-beauty hadrons (BB̄) produced in pp collisions at a centre-of-mass energy of 7 TeV at the CERN LHC is presented, probing for the first time the region of small angular separation. The B hadrons are identified by the presence of displaced secondary vertices from their decays. The B hadron angular separation is reconstructed from the decay vertices and the primaryinteraction vertex. The differential BB̄ production cross section, measured from a data sample collected by CMS and corresponding to an integrated luminosity of 3.1 pb -1, shows that a sizable fraction of the BB̄ pairs are produced with small opening angles. These studies provide a test of QCD and further insight into the dynamics of bb̄ production.