中子诱发典型锕系核素裂变后物理的理论和实验研究

新型核能利用系统的发展对中子诱发锕系核素裂变反应核数据提出了更高的精度要求。本工作提出并构建裂变势驱动模型(Potential-driving model)研究复合核在断裂点时刻的驱动势分布，评价计算中子诱发锕系核素裂变后，发射中子前裂变碎片的质量分布数据。将Potential-driving模型植入Geant4程序，Geant4程序通过调用该模型来模拟中子诱发锕系核素裂变过程，进一步研究Potential-driving模型对裂变后物理描述的科学性和普适性，突破原有Geant4程序的计算限制，理论研究裂变后裂变碎片的性质。同时，研制双屏栅电离室(TFGIC)探测器，实验研究中子诱发锕系核素裂变后物理过程及裂变碎片的性质。最终，将实验测量数据与理论计算数据对比分析，系统地评价给出不同能量中子诱发典型锕系核素裂变后裂变碎片质量分布和动能分布数据，为新型核能利用系统的研发提供可靠的数据支持。

The developments of new nuclear power system put forward the higher accuracy nuclear data for neutron-induced actinide nuclide fission reaction. Based on the systematic model, a global potential-driving model with more well-determined parameters is proposed by uniting the asymmetric fission potential and the symmetric fission potential, which can precisely calculate the driving potential distribution and pre-neutron-emission mass distributions for neutron-induced actinide nuclei fission. Potential-driving model is implanted on Geant4, Geant4 code simulates physical process of neutron-induced actinide nuclei post-fission, which contributes to further research on scientificity and universality, and also break out the limitation for computer capacity. Based on potential-driving model, Geant4 code studies and calculates the mass or charge distributions for independent yields and cumulative yields, kinetic energy distribution and fission neutron spectrum. What’s more, a Frisch-Grid Ionization Chamber detector is developed for experimental research on mass distribution and kinetic energy distribution for neutron-induced actinide nuclei post-fission. Ultimately, compared between experimental measurement data and theoretical data, we evaluate and provide the mass distribution and kinetic energy distribution for neutron-induced actinide nuclei post-fission, which will provide reliable data for the developments of new nuclear power system.