Measurement of B anti-B Angular Correlations based on Secondary Vertex Reconstruction at sqrt(s)=7 TeV.
Journal Article

Published: Monday, March 28, 2011
Citation: Journal of High Energy Physics, Volume 1103, Pages 136
arXiv.org: 1102.3194
Link: http://www.springerlink.com/content/973044328847026g/

Authors (1 total): J. Rohlf

Abstract:

A measurement of the angular correlations between beauty and anti-beauty hadrons ( \textB[`(\textB)] BB) 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 primary-interaction vertex. The differential \textB[`(\textB)] BB 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 \textB[`(\textB)] BB pairs are produced with small opening angles. These studies provide a test of QCD and further insight into the dynamics of \textb[`(\textb)] bb production.