Abstract
The growth and development of "charged particle jets" produced in proton-antiproton collisions at 1.8 TeV
are studied over a transverse momentum range from 0.5 GeV/c to 50 GeV/c. A variety of leading (highest
transverse momentum) charged jet observables are compared with the QCD Monte-Carlo models HERWIG, ISAJET,
and PYTHIA. The models describe fairly well the multiplicity distribution of charged particles within the
leading charged jet, the size of the leading charged jet, the radial distribution of charged particles and
transverse momentum around the leading charged jet direction, and the momentum distribution of charged particles
within the leading charged jet. The direction of the leading "charged particle jet" in each event is used to
define three regions of eta-phi space. The "toward" region contains the leading "charged particle jet", while the
"away" region, on the average, contains the away-side jet. The "transverse" region is perpendicular to the plane
of the hard 2-to-2 scattering and is very sensitive to the underlying event component of the QCD Monte-Carlo models.
HERWIG, ISAJET, and PYTHIA with their default parameters do not describe correctly all the properties of the
"transverse" region.
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