复合核裂变与微观裂变理论进展  

Fission of compound nuclei and the developments of microscopic fission theory

作　　者：裴俊琛[1] PEI JunChen(State Key Laboratory of Nuclear Physics and Technology,School of Physics,Peking University,Beijing 100871,China)

机构地区：[1]北京大学物理学院,核物理与核技术国家重点实验室,北京100871

出　　处：《中国科学：物理学、力学、天文学》2020年第5期25-34,共10页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家重点研发计划(编号:2018YFA0404403);国家自然科学基金(编号:11790325,11835001)资助项目。

摘　　要：核裂变过程是一个复杂的大幅度的量子多体动力学过程,对其理论描述一直是一个挑战.为了描述实验上的裂变可观测量,理论上发展了一些半唯象与近似的模型,但这些模型依赖唯象的参数.从有效核力出发发展微观的裂变理论,原则上无需自由参数,但要达到定量计算的阶段还很困难.本文介绍了复合核裂变的理论进展,特别讨论了微观计算复合核存活概率在超重核合成研究中的关键影响.此外比较了绝热和非绝热的微观裂变动力学模型.其中绝热裂变模型对低激发裂变的实验可观测量能较好描述,而非绝热动力学模型对深入研究裂变机制非常有用.本文分析了核裂变理论的问题和挑战,意识到裂变过程极其复杂,并展望了裂变理论的发展方向.Nuclear fission process is a complex large-amplitude dynamic process of quantum many-body systems, and the development of predictive fission descriptions is a well-known challenge in nuclear physics. To describe the fission observables, there are some phenomenological and semi-microscopic models, which rely on adjustments of parameters.The microscopic fission theory based on effective nuclear interactions in principle can avoid free parameters, but they are not ready for accurate applications. This work discussed about the fission of compound nuclei, which is particularly useful for synthesizing superheavy elements. In addition, we discussed the adiabatic and non-adiabatic microscopic fission models. The adiabatic fission model performs better in describing fission observables, while non-adiabatic fission models are valuable to explore fission mechanisms. We discussed the issues and challenges of current fission theories,and realized the fission process is extremely complicated, and some prospects of fission theory have also been discussed.

关 键 词：核裂变 微观裂变理论 复合核 裂变动力学 

分 类 号：O571.43[理学—粒子物理与原子核物理]