Sensitivity of N/Z ratio in projectile break-up of isobaric systems

Abstract

The binary break-up of projectile-like fragments in non central heavy-ion collisions follows different decay patterns, from equilibrated emission towards dynamical (prompt) fission. Recently, comparing two systems with different N/Z in the entrance channel, it has been shown that the dynamical emission cross-section is enhanced for the most neutron rich system while the statistical emission cross-section is independent from the isotopic composition. In order to understand this dependence and disentangle it from the initial size of the nuclei, we have studied the two isobaric systems 124Xe+64 Zn and 124Xe+64 Ni at 35 A MeV (InKiIsSy experiment), in comparison with the previous studied reactions (124Sn +64 Ni and 112Sn +58 Ni) at the same bombarding energy. We present the first results evidencing a striking similar effect in the dynamical decay as a function of the N/Z of the target for equal size systems.