Quark propagation and hadron formation in the nucleus

Preliminary results of CLAS Experiment 02-104 at Thomas Jefferson National Accelerator Facility will be presented. The main goal of the experiment was to investigate propagation of quarks through strongly interacting systems. Preliminary results will be presented from a series of measurements comparing hadron production from several nuclei (carbon, iron, and lead) in DIS kinematics to that from deuterium. The attenuation of pions and the broadening of their transverse momentum were measured as a function of $Q^2$, $\nu$, $p_{T}^{2}$ and $Z_h$, with very good statistical precision. Qualitativly new results on the electroproduction ``Cronin effect'' will be shown. These measurements are providing a greater understanding of the space-time characteristics of hadronization, and the medium-stimulated emission of gluons by energetic quarks.