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CMS-QCD-10-001 ; CERN-PH-EP-2010-014
First Measurement of the Underlying Event Activity at the LHC with $\sqrt{s}$ = 0.9 TeV
CMS Collaboration
11 June 2010
Eur. Phys. J. C 70 (2010) 555-572
Abstract: A measurement of the underlying activity in scattering processes with pT scale in the GeV region is performed in proton-proton collisions at $\sqrt{s}$ = 0.9 TeV, using data collected by the CMS experiment at the LHC. Charged hadron production is studied with reference to the direction of a leading object, either a charged particle or a set of charged particles forming a jet. Predictions of several QCD-inspired models as implemented in PYTHIA are compared, after full detector simulation, to the data. The models generally predict too little production of charged hadrons with pseudorapidity |h| <2, pT >0.5 GeV/c, and azimuthal direction transverse to that of the leading object.
Links: e-print arXiv:1006.2083 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; Public twiki page ; HepData record ; CADI line (restricted) ;
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Compact Muon Solenoid
LHC, CERN