Dissipative collisions of heavy ions at energies close to the Coulomb barrier

Abstract 208 Pb induced deep inelastic reactions on several target nuclei between 94 Zr and 170 Er have been studied at incident energies close to the Coulomb barrier. From the analysis optimum conditions for the transfer of many nucleons in deep inelastic collisions are deduced. The system 208 Pb + 110 Pd exhibits the largest mass transfer observed so far. This is attributed to the softness of the transitional nucleus 110 Pd. At incident energies close to the barrier the exchange of neutrons is enhanced. The mass, charge and energy flow is analyzed within a model derived from Langevin's theory of Brownian motion. An equilibration phase (~10 −21 s) preceding a diffusion phase was observed. This equilibration phase is controlled by nuclear structure effects. In the later diffusion phase strongly deformed configurations are produced.