Influence of rescattering on the strange particle spectrum

Applying a new method of rescattering which is based on the neural network technique we study the influence of rescattering on the spectra of strange particles produced in heavy ion reactions. In contradistinction to formal approaches the rescattering is done explicitly and not in a perturbative fashion. We present a comparison of our calculations for the system Ni (1.93 A.GeV) + Ni with recent data of the FOPI collaboration. We find that even for this small system rescattering changes the observables considerably but does not invalidate the role of the kaons as a messenger from the high density zone. We cannot confirm the conjecture that the kaon flow can be of use for the determination of the optical potential of the kaon. The experimental results agree with the computations showing a minimal change of the K+ particles in the nuclear matter. Probably, the situation is very different for the K- particles