Probing the decay mechanism of hot nuclei by Coulomb chronometry

Abstract

In this contribution, we propose a new Coulomb chronometer suitable for three-fragment exit channels. We use this chronometer to extract the evolution of the fragment emission time in 129Xe+catSn central collisions from 12 to 25 MeV/A bombarding energy. The involved time scale becomes compatible with simultaneous threefragment break-up above E* = 4.0 ± 0.5 MeV/A, which can be interpreted as the energy required for the onset of multifragmentation.