Determination of Time Scales in Intermediate Energy Reactions

Abstract

The collision between two heavy ions at intermediate and high energies is complicated by the fact that in general not all nucleons participate to the same degree in the interaction. This can be taken into account by attributing the decay products to different sources, representing the highly excited interaction region, and the comparatively cold residual nuclei, respectively. In intermediate energy collisions, especially in the case of small impact parameters, an additional difficulty arises by the fact that these sources are not separated in space but will remain in close contact with each other for some time. In order to compare the results deduced from different decay products we must therefore take into account the different emission times of these ejectiles. In the following two investigations will be discussed where time scales or time hierarchies have been determined.

The experimental data presented in this talk were obtained in collaboration with: K.D. Hildenbrand, W.F.J. Müller, H. J. Rabe, H. Sann, H. Stelzer, W. Trautmann, R. Trockel R. Wada (GSI), N. Brummund, R. Glasow, K.H. Kampert, R. Santo (Univ. Münster), W.M. Eckert, J. Pochodzalla (IKF Frankfurt) and D. Pelte (Univ. Heidelberg).