BACK-REACTION IN THE PRESENCE OF THERMALIZING COLLISIONS

Preequilibrium parton production following an ultrarelativistic nucleu s-nucleus collision is studied in terms of the decay of a strong chrom oelectric field which generates pairs through the Schwinger mechanism. Back-reaction of the partons with the field is included and a model t ransport equation containing a collision term is solved for the centra l rapidity region based on an approximation in which the partons relax to a thermal distribution.