Nowdays, modern microscopic approaches for fission are generally based on the framework of nuclear density functional theory (DFT), which has enabled a self-consistent treatment of both static and dynamic aspects of fission. The key issue is a DFT solver with high precision and efficiency especially for the large elongated configurations. Purpose: To develope a DFT solver with high precision and efficiency based on the point coupling covariant density functional theory (CDFT), which has achieved great success in describing properties of nuclei for the whole nuclear chart. Method: We have extended the point-coupling CDFT to be based on the two-center harmonic oscillator (TCHO) basis, which matches well with the large elongated configurations during the fission process. Multi-dimensional constraint and time-dependent generator coordinate method (TDGCM) have been used to analyze the fission potential energy surface and fission dynamics, respectively. To simulate the splitting process of the nascent fragments beyond scission, we also introduce a density constraint into the new CDFT framework. Results: Illustrative calculations have been done for the PESs and induced fission dynamics of two typical examples: $^{226}$Th and $^{240}$Pu. A more reasonable PES is obtained in the new framework compared to that based on the once-center harmonic oscillator (OCHO) with the same basis space. An optimization of about $0.2\sim0.3$ MeV has been achieved for the outer fission barriers and large elongated configurations. The dynamical simulations based on TCHO basis presents a trend to improve the description for fission yields. Conclusions: The new developed CDFT solver optimizes the elongated configurations, improves the calculation efficiency, and provides a basis for large-scale multi-dimensional constraint calculations and dynamical simulations.
Superheavy nuclei in microscopic collective Hamiltonian approach: the impact of beyond mean field correlations on the ground state and fission properties
Potential Energy Surfaces of Actinide Nuclei from a Multi-dimensional Constraint Covariant Density Functional Theory: Barrier Heights and Saddle Point Shapes
Axially deformed solution of the Skyrme-Hartree-Fock-Bogolyubov equations using the transformed harmonic oscillator basis (III) hfbtho (v3.00): a new version of the program
Potential energy surfaces of actinide and transfermium nuclei from multi-dimensional constraint covariant density functional theories
Multi-dimensional constrained covariant density functional theories were developed recently. In these theories, all shape degrees of freedom β_{λμ} deformations with even μare allowed, e.g., β_{20}, β_{22}, β_{30}, β_{32}, β_{40}, β_{42}, β_{44}, and so on and the CDFT functional can be one of the following four forms: the meson exchange or point-coupling nucleon interactions combined with the non-linear or density-dependent couplings. In this contribution, some applications of these theories are presented. The potential energy surfaces of actinide nuclei in the (β_{20}, β_{22}, β_{30}) deform…
Solution of the Skyrme-Hartree-Fock-Bogolyubov equations in the Cartesian deformed harmonic-oscillator basis. (VIII) hfodd (v2.73y): a new version of the program
弦模型被设计用来提供相对论粒子内部时空结构的协变描述。绳子是一系列像珍珠项链一样的巨大珠子的限制情况。在无限个零质量小球的极限下,它成为场论弦。另一个有趣的限制是通过消除所有其他珍珠来只保留两个珍珠,从而产生谐振子。振荡器模型的基本优点是数学上的简单。这鼓励我们为相对论扩展粒子的协变图像构造双珍珠弦。我们通过变换Feynman { \it et al.}转化为庞加莱群的表示然后,我们为这些振子态构造了类O(3)小群的表示,这决定了它们内部的时空对称性。这个简单的数学过程使我们能够用基本的时空对称性来解释我们在世界上观察到的东西,模型的内在协方差使我们能够用静止框架中的物理来解释无限动量框架中发生的事情。这样就有可能用静止坐标系中的夸克波函数来计算以光速运动的质子内部的部分子分布。
Anharmonicity of multi-octupole-phonon excitations in $^{208}$Pb: analysis with multi-reference covariant density functional theory and subbarrier fusion of $^{16}$O+$^{208}$Pb
Shell structure and orbit bifurcations in finite fermion systems
本文首先介绍了V.M. Strutinsky是A. B. Migdal和合作者。然后,我们更详细地介绍了壳效应的半经典理论,也是Strutinsky根据M。古兹威勒我们特别强调了轨道分叉对壳结构的影响。我们首先给出一个简短的概述半经典的轨迹公式,它连接壳振荡的量子系统与相应的经典系统的周期轨道的总和,在通常被称为“周期轨道理论”。然后,我们提出了一个案例研究中,一个典型的双峰核裂变屏障,包括质量不对称的影响,可以得到的最短周期轨道的腔模型与现实的变形有关的核裂变的总功能。接下来,我们研究壳结构的球形空腔模型,这是可积的,并允许远的分析计算。我们显示,特别是,如何倍周期分岔密切相关的存在所谓的“超变形”的能量最小值,对应于裂变异构体的锕系元素核。最后,我们提出了一类在束缚区域内很好地逼近Woods-Saxon势形状的径向幂律势,给出了它的解析迹公式,并讨论了各种极限(包括谐振子和球箱势).