Jet Fragmentation in Dijet and Gamma-Jet Events

CDF Collaboration
Alexei Safonov
University of Florida
Abstract
Presented are studies of the jet fragmentation at CDF. Average multiplicities and momentum distributions of hadrons in jets are compared to and found to agree with the predictions of Modified Leading Log Approximation, which assumes perturbative nature of the jet fragmentation down to momentum transfer scales as low as k_T ~ \Lambda_QCD. Special attention was paid to extraction of the ratio r of charged particle multiplicities in gluon and quark jets, which was measured both in the context of MLLA calculations and in a model-independent way by analyzing jet-jet and gamma-jet data. The measurements are self-consistent and agree with the perturbative QCD predictions.