Relativistic Calculations for Be-like Iron

Relativistic configuration interaction calculations for the states of 1s²2s², 1s²2s3l (l=s,p,d) and 1s²2p3l (l=s,p,d) configurations of iron are carried out using relativistic configuration interaction (RCI) and multi-configuration Dirac-Fock (MCDF) method in the active interaction approach. In the present calculation, a large-scale configuration expansion was used in describing the target states. These results are extensively compared with other available calculative and experimental and observed values, the corresponding present results are in good agreement with experimental and observed values, and some differences are found with other available calculative values. Because more relativistic effects are considered than before, the present results should be more accurate and reliable.     

全相对论多组态原子结构及物理量的精密计算——构建准完备基以及组态相互作用

从第一原理出发计算原子结构有多种理论方法,它们都是基于变分原理的,其关键是构建一组最适合描述真实物理体系的且适用于变分原理的准完备基.本文阐明了如何利用全相对论计算程序GRASPVU,通过单组态Dirac-Fock计算以及多组态Dirac-Fock自洽场计算建立准完备基.然后利用该准完备基进行组态相互作用计算以充分考虑关联作用;在此基础上,进一步考虑电磁相互作用的延迟效应和量子电动力学等修正.该准完备基对原子结构和电磁跃迁等物理量可进行精密的理论计算.最简单的He体系的能级和跃迁速率等物理量的计算值与目前最准确的理论计算值以及精密的实验测量值符合很好,验证了本文提出的方案的适用性.本文计算是全相对论的,可推广到相对论效应很重要的高Z类He体系,以面向重离子储存环相关实验测量.同时该方案也适用于其他任何多电子原子体系;对Mg进行了精密理论计算,阐明了其33D,43D精细结构次序变化的机理.     

Relativistic Configuration Interaction Calculations on Kα X-Ray Satellites of Manganese

With contributions from Breit interaction, quantum electrodynarnics （QED） corrections and nuclear mass corrections to the initial and final levels are taken into account. The transition energies, transition probabilities, and absorption oscillator strengths of Kα x-ray from Mn XVII to Mn XXIV have been calculated by using relativistic configuration interaction （RCI） and multi-configuration Dirac Fock （MCDF） method in the active interaction approach. Compared with the only available experimental transition data on He-like and Li-like manganese, the present results are in good agreement with them, and the rest of transition data of the present results are new ones. These wide range data can provide useful parameters for the study of the manganese plasma.     

弛豫与关联效应对NII离子2s22p3s3P1—2s22p21D2与2s22p3s1P1—2s22p23P0,1,2自旋禁戒跃迁概率的影响

用多组态Dirac-Fock方法，并系统考虑相对论效应、电子关联、弛豫效应等重要贡献，计算了NII离子2s22p3s 3P1—2s22p21D2和2s22p3s 1P1—2s22p23P0,1,2自旋禁戒跃迁概率和振子强度-通过比较计算证实：弛豫和关联效应对禁戒跃迁概率的影响非常大，考虑了这些效应后，计算结果有显著的改善-由跃迁概率和振子强度的计算值推断，2s22p3s 3P1—2s22p21D2的谱线强度应该比原有的理论预言值小- 关键词： 跃迁概率 多组态Dirac-Fock方法     

NⅡ离子2p4f—2p3d辐射跃迁概率的理论研究

在全相对论理论框架下，利用多组态Dirac-Fock(MCDF)方法，系统计算了NⅡ离子2p4f—2p3d的辐射跃迁概率，得到的结果与已有实验值符合很好.具体计算中，详细分析了相对论效应、电子关联、弛豫效应、Breit相互作用和量子电动力学(QED)效应对能级精细结构及辐射跃迁概率的影响.结果表明：相对论效应、电子关联和弛豫效应对NⅡ 2p4f-2p3d辐射跃迁概率有很重要的影响,考虑了这些效应后计算值得到明显改善.     

Systematical Study on Ground-State Ionization Potentials for Boron andCarbon Isoelectronic Sequences with Z=6-42

The multi-configuration Dirac-Fock method is used in this work to calculateground-state ionization potentials of Boron and Carbon isoelectronicsequences from Z=6 to Z=42. And the contribution of relativisticcorrections, nuclear volume effect, Breit and QED effects to the results isdiscussed in the calculation. The results are compared with the scantyexisting theoretical and experimental data in the literature and goodagreements are achieved. Then analytical expressions of Ionization potentialalong Boron and Carbon isoelectronic sequences are obtained.     

关于极端原子核的相对论自洽角动量投影壳模型计算(英文)

相对论自洽角动量投影壳模型是最近发展出来的一个自洽模型, 它对于不同核区具有稳定的参数, 能够很好地描述已知和未知具有稳定形变的各种原子核的性质。 计算了若干包括稳定核素、 极端核素和超重核素, 并把计算结果与现有的实验数据进行了比较。     

电子相关对Xe10+离子4d8—4d75p跃迁系跃迁概率的影响

应用多组态Dirac-Fock(MCDF)方法,对Xe¹⁰⁺离子进行了理论计算,获得了跃迁波长和概率等数据.通过逐步引入4dⁿ—5pⁿ(n=1, 2, 3)电子相关的相互作用组态,重点研究了电子相关效应对4d⁸—4d⁷5p跃迁系跃迁概率的影响.结果显示电子相关效应显著,表明了欲得到精确的4d⁸—4d⁷5p的振子强度(跃迁概率)数据,理论计算中至少要包括到4d²—5p²的电子相关组态的影响.与实验测得的跃迁波长比较发现,理论结果与之有着较好的一致性;同时理论跃迁概率在两种规范下的结果符合得相当精确,显示了计算结果的可靠性. 关键词： 多组态Dirac-Fock(MCDF)方法 电子相关 跃迁概率     

ThLⅩⅩⅩⅢ和ULⅩⅩⅩⅤ离子的能级和相干辐射波长计算

本文用相对论多组态Ｄｉｒａｃ－Ｆｏｃｋ广义平均能级（ＭＣＤＦ－ＥＡＬ）模型计算了自然界中天然存在的重稳定元素Ｔｈ和Ｕ的类氧离子能级和相干辐射波长值。     

类铍离子1s22s2p 3P1, 2 能级之间的磁偶极跃迁

用多组态Dirac-Fock和相对论组态相互作用的扩展优化能级方法,在计算中包含了Breit相互作用,真空极化,自能以及有限核质量修正,计算了核电荷数从Z=6到80的类铍离子等电子序列的1s22s2p 3P1, 2的精细结构能级,磁偶极跃迁几率和振子强度。结果与目前可靠的结果在其不确定度范围内符合得很好,另外也得到一些与其他早期理论计算不同的结果。     

Superthermal Electron Produced in Relativistic Laser-Plasma Interaction

The dynamics of a relativistic electron submitted to an intense, plane wave, linearly polarized laser field is reviewed. Based on the dynamics, the temperature of the electron in the laser field is defined and calculated. It is found that the calculated temperature fits the first temperature observed in the experiment by Malka et al. A model to evaluate the electron temperature by taking the electron-ion scattering into account is proposed. It is found that when I≥4.0×10¹⁸ W/cm² the electron temperature by considering the scattering, T_h^s, is evidently larger than the electron temperature without considering the scattering, T_h. This result is in favor of explaining the two-temperature distribution of the electron energy observed in the experiment by Malka et al.     

类铍CⅢ 和 OⅤ离子激发态的相对论能量和跃迁几率

利用多组态相互作用方法及Rayleigh-Ritz变分法,计算了类铍CⅢ和OⅤ离子激发态1s22s2p1P0,1s22s2p3P0,and 1s22p2 3P的能量,包括了相对论能量和质量极化效应。计算了相关态的振子强度、跃迁几率和波长。计算结果与其它理论和实验结果符合得很好。     

Superthermal Electron Produced in Relativistic Laser-Plasma Interaction

The dynamics of a relativistic electron submitted to an intense, plane wave, linearly polarized laser field is reviewed. Based on the dynamics, the temperature of the electron in the laser field is delined and calculated. It is found that the calculated temperature fits the first temperature observed in the experiment by Malka et al. A model to evaluate the electron temperature by taking the electron-ion scattering into account is proposed. It is found that when I ≥ 4.0 × 101s W/cm2 the electron temperature by considering the scattering, T hs, is evidently larger than the electron temperature without considering the scattering, Th. This result is in favor of explaining the two-temperature distribution of the electron energy observed in the experiment by Malka et al.     

Relativistic Calculations for Trapped Ions

We present recent results in the field of total binding energy calculations, Landщ factors, quantum electrodynamics corrections and lifetime that are of interest for ion traps and ion sources. We describe in detail MCDF and RMBPT calculation of ionic binding energies, which are needed for the determination of atomic masses from highly charged ion measurements. We also show new results concerning Landщ factor in 3-electron ions. Finally we describe how relativistic calculations can help understand the physics of heavy ion production ion sources. This revised version was published online in July 2006 with corrections to the Cover Date.     

Large scale multi-configuration Hartree-Fock calculation of the hyperfine structure of the ground state of vanadium

The hyperfine structure of the ground state of vanadium, ⁵¹VI, is calculated in the nonrelativistic framework of the multi-configuration Hartree-Fock approximation. A configuration state function limiting algorithm is used to make the calculations feasible and to study the influence of core, valence and core-valence correlations in detail. The obtained configuration state function space captures the most important orbital correlations within 2%. Further correlations are included through configuration interaction calculation. The atomic state functions are used to evaluate the magnetic dipole hyperfine factor A and the electric quadrupole factor B. It turns out that the ab initio calculation can not capture the core polarization of the 2s shell. It introduces an error that is higher than the Hartree-Fock approximation. However, the detailed correlations being observed suggest the introduction of a wrong correlation orbital due to the algorithm being used. Neglecting this orbital leads to good agreement with 2% deviation from the experimental values for the A factors.     

Relativistic nonlinearity and wave-guide propagation of rippled laser beam in plasma

In the present paper we have investigated the self-focusing behaviour of radially symmetrical rippled Gaussian laser beam propagating in a plasma. Considering the nonlinearity to arise from relativistic phenomena and following the approach of Akhmanov et al, which is based on the WKB and paraxial-ray approximation, the self-focusing behaviour has been investigated in some detail. The effect of the position and width of the ripple on the self-focusing of laser beam has been studied for arbitrary large magnitude of nonlinearity. Results indicate that the medium behaves as an oscillatory wave-guide. The self-focusing is found to depend on the position parameter of ripple as well as on the beam width. Values of critical power has been calculated for different values of the position parameter of ripple. Effects of axially and radially inhomogeneous plasma on self-focusing behaviour have been investigated and presented here.     

对Λ超核的相对论平均场计算

使用新的相对论平均场力参数TW1和ML-SH对A超核的基态性质进行了研究,发现上述参数能得到Λ超核令人满意的理论结果,两套参数的结果差别不大,特别是Λ超核的结果不依赖于有效核子一核子相互作用力参数,在研究超核中考虑了对关联的影响,发现它导致了奇偶效应.     

球坐标动量空间下相对论Vlasov方程的数值算法

针对相对论Vlasov方程动量区间跨度大、难以计算的困难,将相对论Vlasov方程在球坐标动量空间中进行数值求解.对相对论Vlasov方程球坐标动量空间构造4阶非分裂守恒型数值格式.数值模拟相对论Landau阻尼问题并与解析理论进行比较,验证数值模型和算法的有效性.对激光等离子体相互作用进行初步模拟分析,表明通过采用球坐标下的动量空间,可在相对较少动量网格情形下,获得与粒子模拟可相互验证的结果.     

原子核结构的相对论第一性原理研究

过去几十年中,原子核物理的相对论密度泛函理论得到很大发展,可以成功地描述各种原子核现象。文章阐述在相对论框架下研究原子核多体问题的必要性,介绍原子核物理中相对论密度泛函理论的基本概念,回顾相对论密度泛函理论在描述原子核基态、手征转动和动力学过程等方面的应用,讨论基于原子核物理的相对论第一性原理研究,即完全自洽的相对论Brueckner—Hartree—Fock理论,构建微观普适的密度泛函的基本思想。     

钡原子6s~2、5d~2、6p~2组合的电子相关效应及其组合相互作用

用模型势方法和斯莱特-高登(Slater-Condon)理论计算了钡原子偶宇称6s~2,5d~2,6p~2电子组合、角动量J=0,1,2的双激发能级的激发能和组合相互作用(configuration interaction)。结果表明,6s~2,5d~2和6p~2组合在~1S_0态中强烈地混合,使常规能级标识符号失去意义。另外,我们的结果也从理论上证明了曾引起争议的6p~(21)S_0能级是位于第一电离势之上的自由离能级。