Test particle description of transport processes for states with a continuous mass spectrum

Abstract

Aiming at a description of transport processes where the dynamically generated width of the states is potentially large a transport equation beyond the quasiparticle approximation is derived in first order gradient expansion. An effective particle number is identified which is exactly conserved by the coarse grained transport equation. Using a test particle ansatz for this conserved quantity allows to rewrite the transport equation into equations of motion for test particles. The two-body collision terms are formulated in terms of the test particles which gain non-trivial renormalization factors due to the coarse graining process.

Comments: 10 pages, LaTeX, no figures, Talk given at the workshop ``Kadanoff-Baym Equations --- Progress and Perspectives for Many-Body Physics'', Rostock, Germany, 20.-24. September 1999