STUDY OF MULTIFRAGMENTATION PATTERNS INDUCED BY SPINODAL INSTABILITIES

In this article we study the characteristics of multifragmentation pat terns induced by spinodal instabilities using a stochastic mean-field approach. For two-dimensional unstable nuclear matter, we find that th e early fragmentation process occurs accordingly to few dominant unsta ble wavelengths, This favours the partition of the system in close-mas s pieces, with a lack of very small fragments, Then, we consider the r ealistic case of spherical systems initialized at low density. The rol e of finite-size effects, final-state interaction and secondary decay is carefully investigated. We discuss under which conditions some memo ry of the first dynamical stage survives in the final fragment partiti ons.