Modeling of compound nucleus formation in the fusion of heavy nuclei

A new model that includes the time-dependent dynamics of the single-particle motion in conjunction with the macroscopic evolution of the system is proposed for describing the compound nucleus formation in fusion of heavy nuclei. The diabaticity initially keeps the entrance system around its contact configuration, but the gradual transition from the diabatic to the adiabatic potential energy surface leads to fusion or quasifission. Direct measurements of the probability for compound nucleus formation are crucial to discriminate between the current models.

Figure 1

Dynamical PES for ${}^{110}\mathrm{Pd}+{}^{110}\mathrm{Pd}:$ (upper part) at $t=0\mathrm{s}$ (diabatic PES), the square denotes the contact configuration; (middle part) at $t_0=4\times {10}^{-20}\mathrm{s}$; and (lower part) the adiabatic PES. See text for further details.

Figure 2

Distribution of the population probabilities $p(\lambda ,\xi ,t_0)$ for ${}^{110}\mathrm{Pd}+{}^{110}\mathrm{Pd}$ on the PES of Fig. 1 (middle part). The fusion region is $\lambda \le 1.3$. See text for further details.