In the context of the `jet quenching phenomena typically materialization of the jet is assumed to take place in vacuum outside the reaction zone. On the other hand quantum mechanical estimates give a hadronization time on the order of only a few fm/c for jets materializing into hadrons with transverse momenta of $pT{} leq 10 GeV$, which thus should well take place inside the fireball. Typical (in-)elastic collisions of these high $pT{}$ particles with the bulk of hadrons of the fireball have a rather low invariant mass and are thus nonperturbative. An analysis within an opacity expansion in the number of collisions by means of the FRITIOF collision scheme for various hadrons will be presented. It shows that late hadronic collisions can substantially account for the modification of the high $pT{} $-spectrum observed for central collisions at RHIC.
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