Probing the Dissipation Mechanism in Ternary Reactions of ¹⁹⁷Au+¹⁹⁷Au by Mean Free Path of Nucleons

the collision of very heavy nuclei ¹⁹⁷Au+¹⁹⁷Au at 15 A MeV has been studied within the improved quantum molecular dynamics model. A class of ternary events satisfying nearly complete balance of mass numbers is selected. The experimental mass distributions for the system ¹⁹⁷Au+¹⁹⁷Au ternary fission fragments, the heaviest (A₁), the intermediate (A₂) and the lightest (A₃), are reproduced well. The mean free path of nucleons in the reaction system is studied and the shorter mean free path is responsible for the ternary fission with three mass comparable fragments, in which the two-body dissipation mechanism plays a dominant role.