原子核低激发谱与量子相变的协变密度泛函研究

项目名称： 原子核低激发谱与量子相变的协变密度泛函研究

项目编号： No.11475140

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 李志攀

作者单位： 西南大学

项目金额： 80万元

中文摘要： 原子核量子相变涉及新的动力学对称性、原子核壳结构演化及介观系统相变的有限粒子数效应等重要科学问题，是核物理近年来的研究热点课题之一。原子核低激发谱对于深入认识原子核量子相变以及揭示其微观机制至关重要。特别是，随着加速器的升级换代和探测设备的改进，人们观测到越来越多的奇特核谱学信息，为系统研究原子核量子相变提供了良好的平台。本项目基于过去的工作基础，针对以上热点问题，拟开展以下研究工作：1）发展适用于奇核低激发谱的协变密度泛函理论，自洽包含四极及八极形变自由度，实现对中重原子核低激发谱的统一、微观、自洽描述；2）研究价核子-核芯耦合效应及四极-八极关联效应，分析势能曲面及相变序参量演化规律，揭示相变临界点及动力学对称性；3）系统研究原子核四极、八极形状相变，探讨相变的一般规律及微观机制；4）微观研究奇特核与超重核低激发谱，自洽描述奇特核结构新特性，探索超重核形状演化规律及微观壳结构特征。

中文关键词： 原子核结构；协变密度泛函理论；奇特原子核；量子相变；低激发态

英文摘要： Nuclear quantum phase transition (QPT) becomes one of hot topics in nuclear physics in recent years, because it is related to the new dynamical symmetry,evolution of shell structure,finite size effect on QPT in mesoscopic system, and so on.The low-lying spectrum is very important to help us to understand the nuclear QPT deeply and the corresponding microscopic mechanism.In particular, more and more measurements have been performed for the spectra of exotic nuclei due to the update of the accelerator and detector. This is benifit for the systematic investigations on the QPT in complex systems. Based on our previous work, the project will focus on the following studies to understand the above hot topics: 1) Development of a core-quasiparticle coupling model based on the covariant density functional theory, including both quadurpole and octupole degrees of freedom, that can provide a systematic description for the low-lying spectra of the medium-heavy and heavy nuclei. 2) The effects of nucleon-core coupling and quadrupole-octupole coupling on the low-lying spectrum. Analyze the evolution of the potential energy surfaces and order parameters along the isotopic chain, and try to reveal the critical points and corresponding dynamical symmetries. 3) Systematic study of the quadrupole and octupole shape phase transitions. Discuss the general properties and microscopic mechanism of nuclear QPT. 4) Microscopic analysis of low-lying spectra in exotic nuclei and superheavy nuclei. Describe the new exotic structure in exotic nuclei self-consistently. Explore the shape evolution and possible shell/subshell closure in superheavy nuclei.

英文关键词： Nuclear Structure;Covariant Density Functional Theory;Exotic Nuclei;Quantum Phase Transition;Low-lying Spectrum