Inclusive momentum distributions of charged particles in
restricted cones around jet axes were measured in dijet events with
invariant dijet masses in the range 80 to 600 GeV/c2. Events were produced
at the Tevatron in p anti-p collisions with center of mass energy of 1.8 TeV
and recorded by the Collider Detector at Fermilab. The results were
compared to perturbative QCD calculations carried out in the framework of
the Modified Leading Log Approximation (MLLA) and assuming Local
Parton-Hadron Duality (LPHD). It was shown that the data follow theoretical
predictions quite well over the whole range of the jet energies included in
this analysis. We extracted the MLLA cut-off scale Q_eff and found a value
of 230 +/- 40 MeV. The theoretical prediction of E_jet sin Theta_c scaling,
where Theta _c is the cone opening angle, was experimentally observed for
the first time. From the MLLA fits to the data, two more parameters were
extracted: the ratio of parton multiplicities in gluon and quark jets, r =
Ng-jet_partons/Mq-jets_partons = 1.9 +/- 0.5, and the ratio of the number
of charged hadrons to the number of predicted partons in a jet,
Kcharged_LPHD = Ncharged_hadrons/N_partons = 0.56 +/- 0.10.
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Updated: Monday, 2003 July 28 15:00:00 CDT automatically from input from "Carol I. Picciolo"