Multifragmentation of XE(50A MEV)+SN Confrontation of Theory with Data

Abstract

We investigate the properties of small (quantum) systems and study how they can be observed. In quest of the physical origin of multifragmentation, observed in collisions between heavy ions, we investigate whether the experimental observables allow to distinguish between two proposed scenarios, that multifragmentation is a fast process, driven by the reaction dynamics or a very slow process caused by the spinodal decomposition of an equilibrated expanding system. We arrive at the conclusion that contrary to common believe both scenarios give very similar results. We also show that the system is too small for being treated in a canonical approach. Hence temperature and chemical potential cannot be defined in a meaningful way.