热核表面能的Thomas–Fermi统计模型理论

用Seyler-Blanchard动量相关非定域相互作用的含温Thomas-Fermi统计理论,对半无穷大核物质模型计算了核物质表面能系数σ(T,δ)随温度T和不对称度δ的变化,发现在低温T≤5MeV和不对称度δ≤0.2时,可以近似写成σ(T,δ)=σ₀(T)[1+K(T)δ²],其中σ₀(T)和K(T)可以拟合成温度T的二次函数.     

The virial theorem in refined Thomas－Fermi－Dirac theory for the interior of atoms in a solid

The virial theorem in refined Thomas－Fermi－Dirac theory for the interior of atoms in a solid is given and proven.     

热核静态性质的一个简单模型

以扩展Skyrme力为基础,计入唯象的表面效应和Coulomb相互作用,推导了核系统的能量密度。对于有限温度情形,通过索末菲展开,得到了能量密度、自由能密度以及熵密度的解析公式。由此计算了热核物质和有限核的状态方程,每核子熵及每核子自由能。对计算结果作了比较和分析,预言了在同一框架下研究热核动力学演化的可能性。 关键词：     

推广的Thomas－Fermi方法中适用的新式核密度

给出一种适用于推广的Ｔｈｏｍａｓ－Ｆｅｒｍｉ方法（ＥＴＦ）的密度形式．取ＳｋＭ势参量，对几个球形核的基态性质进行了计算，结果优于通常采用的多参数密度形式．用期望值方法（ＥＶＭ）给出的基态能量能重现Ｈ—Ｆ的计算结果．     

25MeV/u~(40)Ar ~(93)Nb反应中热核的激发能和核温度

利用半导体望远镜探测器和ＰＰＡＣ对２５ＭｅＶ／ｕ４０Ａｒ＋９３Ｎｂ反应中的带电粒子和余核进行了关联测量，对所得α粒子能谱用三源模型进行了拟合，并由余核飞行时间和粒子多重性得到热核激发能．通过对温度的修正，发现在本实验中有激发能Ｅ＊／Ａ为４．３ＭｅＶ，温度Ｔｉｎｉｔ为６．９ＭｅＶ的热核形成。通过与其它实验结果的对比可以看出核物质在轻系统和重系统中行为的差异。     

Ionization of Atoms and the Thomas－Fermi Model for the Electric Field in Crystal Planar Channels

The electric field in the crystal planar channels is studied by the Thomas-Fermi method.The ThomasFermi equation and the corresponding boundary conditions are derived for the crystal palanar channels,The numerical solution for the elctric field in the channels between(110) Planes of the single crystal silicaon and the critical angles of channelling protons in them are shown.Reasonable agreements with the experimental data are obtained.The results show that the Thomas-Fermi method for the crystal works well in this study,and a microscopic research of the channel electric field with the contribution of all atoms and the atomic ionization being taken into account is practical.     

Fermi—Dirac关联与Q~（－v）K_v（Q）分布

根据非微扰理论提出一种源分布─—Ｑ－ｖＫｖ（Ｑ）分布．由此计算两质子的Ｆｅｒｍｉ－Ｄｉｒａｃ关联．拟合的曲线与实验数据吻合得较好，这是Ｑ－ｖＫｖ（Ｑ）分布比Ｇａｕｓｓ源分布优越之处．由全同质子的Ｆ—Ｄ关联计算出发射源半径及Ｆｅｒｍｉ场的反常量纲．     

25MeV/u 40Ar+93Nb反应中热核的激发能和核温度

利用半导体望远镜探测器和PPAC对25MeV/u ⁴⁰Ar+⁹³Nb反应中的带电粒子和余核进行了关联测量,对所得α粒子能谱用三源模型进行了拟合,并由余核飞行时间和粒子多重性得到热核激发能.通过对温度的修正,发现在本实验中有激发能E^*/A为4.3MeV,温度T_init为6.9MeV的热核形成.通过与其它实验结果的对比可以看出核物质在轻系统和重系统中行为的差异.     

热核多重碎裂与液-气相变的新进展

回顾了热核研究的基本理论方法和液－气相变的研究历史,对近年有关研究的进展作了评述,指出了将来进一步研究的主要方向． The basic theoretical methods for investigating the hot nuclei and their multifragmentation are reviewed. After the history of the studies of the liquid gas phase transition is introduced briefly, the comments on its new advances are given. The main frontiers in the corresponding fields are pointed out as well.     

热核动力学演化的一个简单模型

以半经验的能量密度为基础,利用Fermi-Dirac积分的低温展开,得到了核的状态方程P(S,ρ)。在绝热假定下,采用流体动力学方程,具体研究了不同的热压缩核的动力学演化,特别分析了热能和压缩能对热压缩核稳定性的影响。 关键词：     

热核的衰变动力学研究

在Vlasov框架下讨论了高温、高压缩核物质的动力学演化过程.通过研究得出,初始过程对碎裂的影响很大,这里密度的影响比热激发能的影响更大.在相同的初始条件下,不可压缩系数对碎裂过程影响很大,即热核在硬势的平均场中比在软势的平均场中更易裂开     

热核的热稳定曲线

从核极限温度的角度研究了热核的热稳定性.采用Skyrme相互作用力计算热核同位素的极限温度,得到的极限温度的同位素分布呈现出倒置抛物线的趋势,与中能重离子反应多重碎裂中同位素产额分布的实验结果具有一致的行为表现.系统地计算了从轻到重的一系列元素极限温度的同位素分布,并从中抽取出热核的热稳定曲线.与β稳定线相比,热核的热稳定线更加偏丰中子.     

35MeV/u 40Ar+197Au反应中热核的统计发射研究

利用硅半导体+CsI(T1)闪烁体望远镜测量35MeV/u ⁴⁰Ar+¹⁹⁷Au中发射的轻带电粒子,用能谱斜率方法和双同位素产额比方法提取了核温度参量.研究了热核发射过程中的统计发射规律.     

Ground State Properties of Superheavy Nuclei in Macroscopic-Microscopic Model

The ground state properties of superheavy nuclei are systematically calculated by the macroscopic- microscopic （MM） model with the Nilsson potential. The calculations well produced the ground state binding energies, α-decay energies, and half lives of superheavy nuclei. The calculated results are systematically compared with available experimental data. The calculated results are also compared with theoretical results from other MM models and from relativistic mean-field model. The calculations and comparisons show that the MM model is reliable in superheavy region and that the MM model results are not very sensitive to the choice of microscopic single-particle potential.     

Evaluation of Coulomb Energy Difference for Light Mirror Nuclei Using Slater—Type Orbitals

Behavior of the Coulomb energy difference for light nuclei is explained in terms of the different values of the average Coulomb interaction between two particles.Coulomb energy difference according to shell model of light mirror nuclei in the Coulomb and exchange integrals in the formula can be explained with exponential-type wavefunctions.In this study,using the one-center expansion of exponential-type wavefunctions in terms of Slater-type orbitals with the same center,we derived formula for Coulomb energy difference of light mirror nuclei.     

Coulomb effect in rotating nuclei in the Thomas-Fermi approach

The effect of nuclear Coulomb potential in rotating nuclei has been studied in the Thomas-Fermi approach. The numerical calculations of typical rotating nuclei show that Coulomb potential plays an important role in the rotational mass regions 150–190 and >224.     

相对论平均场框架下偶-偶核奇-偶核计算误差的系统研究

在相对论平均场理论框架下, 用NL-3和NL-Z两组相互作用参数研究了4个同位素链²⁸Ni,⁵⁴Xe,⁷⁸Pt,⁹⁴Pu的基态性质. 发现,在Hatree近似下奇A核结合能理论计算值与实验值的相对误差反而普遍比偶偶核小. 这说明用相对论平均场理论,即使不考虑矢量介子的空间分量,仍可以比较可靠地计算奇A核结合能.     

Solution of the Thomas-Fermi problem for continuous,spherical, positive charge distribution

A method to make anab initio calculation of the free energy of small drops of liquid metal is presented. The model chosen involves the replacing of the positive ion cores by an equivalent continuous spherical distribution of charge. The Thomas-Fermi potential is calculated as a starting point for a Hartree-Fock self-consistent field calculation. The results of the Thomas-Fermi calculation are reported as an example of the preliminary calculations.Research supported under NSF Grant #20884.     

复杂粒子发射对热核巨共振的影响

讨论了引起统计蒸发模型计算结果与高温热核偶极巨共振实验结果之间存在差别的因素,对比了标准CASCADE程序计算结果与加入复杂粒子发射后的计算结果,计算显示复杂粒子发射对高温热核偶极巨共振的性质有影响.