Observation of long-range, near-side angular correlations in proton-proton collisions at the LHC


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

JOURNAL OF HIGH ENERGY PHYSICS, no.9, 2010 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: Issue: 9
  • Publication Date: 2010
  • Doi Number: 10.1007/jhep09(2010)091
  • Journal Name: JOURNAL OF HIGH ENERGY PHYSICS
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Keywords: Hadron-Hadron Scattering, FLOW

Abstract

Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center-of-mass energies of 0.9, 2.36, and 7TeV are presented, using data collected with the CMS detector over a broad range of pseudorapidity (eta) and azimuthal angle (phi). Short-range correlations in Delta(eta), which are studied in minimum bias events, are characterized using a simple "independent cluster" parametrization in order to quantify their strength (cluster size) and their extent in eta (cluster decay width). Long-range azimuthal correlations are studied differentially as a function of charged particle multiplicity and particle transverse momentum using a 980 nb(-1) data set at 7TeV. In high multiplicity events, a pronounced structure emerges in the two-dimensional correlation function for particle pairs with intermediate p(T) of 1-3 GeV/c, 2.0