重核融合反应动力学位垒的微观研究

在简要评述重核融合过程中几种主要理论模型的基础上,提出了微观输运动力学模型,即改进的量子分子动力学模型.在这个模型的框架内,我们研究了重核融合位垒的动力学行为.我们发现,随入射能量的减少,可以得到最低的动力学位垒,它趋近于绝热静态位垒.而随入射能量的增加,动力学位垒增加,最后趋近于非绝热静态位垒,这给出了位垒分布的两个边缘.在微观输运动力学模型基础上,我们还研究了在融合路径上,动力学位垒与融合体系微观构型的关系.考虑到融合过程不同时刻的单粒子位势与双中心壳模型位势的相似性,我们可以很好的研究融合过程中,在构型空间里单粒子态及相关量的时间演化行为.

Microscopic Study on Dynamic Barrier in Fusion Reactions

In this paper we briefly review the fusion process of very heavy nuclear systems and some theoretical models. We propose a microscopic transport dynamic model, i.e. the Improved Quantum Molecular Dynamic model, for describing fusion reactions of heavy systems, in which the dynamical behavior of the fusion barrier in heavy fusion systems has been studied firstly. We find that with the incident energy decreasing the lowest dynamic barrier is obtained which approaches to the adiabatic static barrier and with increase of the incident energy the dynamic barrier goes up to the diabatic static barrier. We also indicate that how the dynamical fusion barrier is correlated with the development of the configuration of fusion partners along the fusion path. Associating the single-particle potentials obtained at different stages of fusion with the Two Center Shell Model,we can study the time evolution of the single particle states of fusion system in configuration space of single particle orbits along the fusion path.