  We discuss the effects of the off-shell nucleon propagation for the particle
production. Results from nonequilibrium Kadanoff-Baym evolution modeling a
heavy ion collision are presented. The production rates are compared to
equilibrium emission rates obtained in the same approximation for the
self-energy. The comparison of semiclassical and quantum in-medium production
rates is performed within the T-matrix approximation. Self-consistent T-matrix
resummation allows us to discuss also the effect of the off-shell propagation
on the effective in-medium cross section.
