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1.
The differential and integral cross sections for electron impact excitation of lithium from the ground state 1s22s to excited states 1s22p, 1s23l (l=s, p, d) and 1s24l (l=s, p, d, f)at incident energies ranging from 5 eV to 25 eV are calculated by using a full relativistic distorted wave method. The target state wavefunctions are calculated by using the Grasp92 code. The continuum orbitals are computed in the distorted-wave approximation, in which the direct and exchange potentials among all the electrons are included. A part of the cross sections are compared with the available experimental data and with the previous theoretical values. It is found that, for the integral cross sections, the present calculations are in good agreement with the time-independent distorted wave method calculation, for differential cross sections, our results agree with the experimental data very well.  相似文献   

2.
A programme is developed to calculate the polarizations of the radiation emitted after electron impact excitation. The fully relativistic distorted-wave method is used in cross-section calculations. The programme is applied to He- and Li-like ions. The calculated values of line polarization are compared with other theoretical results and experimental values. For He-like U, at lower incident energy, the present polarization agrees with the other theoretical ones within 1%, while at higher energy, the differences increase up to about 10%. For He-like Fe and Ti, the present results of polarization degree for most of the lines agree with the experimental data within the experimental error bars. For the Li-like Ti line q (ls2s2p^2p3/2 to ls^22s), the present value of the polarization agree excellently with another theoretical one, and both the values are consistent with the measured data within the experimental error bar.  相似文献   

3.
The variational method using a multiconfiguration wavefunction is carried out on the core-excited state 1s2s2p 4P0 for helium negative ion,including mass polarization and relativistic corrections.Binding energy and fine structure are reported.The results are compared with other theoretical and experimental date in the literature.  相似文献   

4.
程诚  高翔  青波  张小乐  李家明 《中国物理 B》2011,20(3):33103-033103
Using the multi-configuration Dirac-Fock self-consistent field method and the relativistic configuration-interaction method,calculations of transition energies,oscillator strengths and rates are performed for the 3s 2 1 S 0-3s3p 1 P 1 spinallowed transition,3s 2 1 S 0-3s3p 3 P 1,2 intercombination and magnetic quadrupole transition in the Mg isoelectronic sequence(Mg I,Al II,Si III,P IV and S V).Electron correlations are treated adequately,including intravalence electron correlations.The influence of the Breit interaction on oscillator strengths and transition energies are investigated.Quantum electrodynamics corrections are added as corrections.The calculation results are found to be in good agreement with the experimental data and other theoretical calculations.  相似文献   

5.
The x-ray energies and transition rates associated with single and double electron radiative transitions from the double K hole state 2s2p to the 1s2s and 1s^2 configurations of 11 selected He-like ions(10 ≤ Z ≤ 47) are calculated using the fully relativistic multi-configuration Dirac–Fock method(MCDF). An appropriate electron correlation model is constructed with the aid of the active space method, which allows the electron correlation effects to be studied efficiently. The contributions of the electron correlation and the Breit interaction to the transition properties are analyzed in detail. It is found that the two-electron one-photon(TEOP) transition is correlation sensitive. The Breit interaction and electron correlation both contribute significantly to the radiative transition properties of the double K hole state of the He-like ions. Good agreement between the present calculation and previous work is achieved. The calculated data will be helpful to future investigations on double K hole decay processes of He-like ions.  相似文献   

6.
Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l (l = s,p,d) and 1s^22p31 (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.  相似文献   

7.
A fully relativistic distorted-wave program is developed based on the Grasp92 and Ratip packages to calculate electron impact excitation (EIE) cross sections. As a first application of the program, the EIE cross sections of Be-like C^α+ ions from the metastable 1s^22s2p^3 p to 1s^22p^2 ^3 p excitation and the inner-shell excitations are calculated systematically. Meanwhile, the correlation effects of target states are discussed. It is found that the correlation effects play an important role in the low energy EIE cross sections. An excellent agreement is found when the results are compared with previous calculations and recent measurements.  相似文献   

8.
We focus on the full relativistic quantum mechanical calculations from boron to fluorine atoms with electronic configuration of 1s2 2s2 2p n(n =1,2,3,4,and 5),where 1s2 2s2 is the closed shell and 2p n is the open shell.Their active electrons in the open shell occupy all the six spinors as far as possible.Therefore,we suggest a new rule called "maximum probability" for the full symmetry group relativistic theory.Furthermore,the spectral fine structure of the atomic ground states based on the full relativistic theory and their intervals of L-S splitting are all reasonable.It is impossible to calculate the L-S splitting through non-relativistic quantum mechanics.The relativistic effect of atomic mass is increased significantly by about 12 folds from boron atom to fluorine atom.  相似文献   

9.
Energy levels, wavefunction compositions and lifetimes have been computed for all levels of 1s22s22p5, 1s22s2p6,1s22s22p43 s, 1s22s22p43 p, and 1s22s22p43 d configurations in highly charged F-like tungsten ion. The multiconfigurational Dirac–Fock method(MCDF) is adopted to generate the wavefunctions. We have also presented the transition wavelengths,oscillator strengths, transition probabilities, and line strengths for the electric dipole(E1) and magnetic quadrupole(M2)transition from the 1s22s22p5 ground configuration. We have performed parallel calculations with the flexible atomic code(FAC) for comparing the atomic data. The reliability of present data is assessed by comparison with other theoretical and experimental data available in the literature. Good agreement is found between our results and those obtained using different approaches confirm the quality of our results. Additionally, we have predicted some new atomic data for F-like W that were not available so far and may be important for plasma diagnostic analysis in fusion plasma.  相似文献   

10.
Electron impact excitation cross sections from the ground state to the individual magnetic sublevels of 1s2p 3'1P1 states in high-temperature dense plasmas are calculated for highly charged He-like Fe24+ ions by using a fully relativistic distorted-wave method. The Debye-Huckel screening model is used to screen the projectile electron from the nucleus and target electrons. The linear polarization degrees for these lines are obtained. It is found that the cross sections at all incident energies decrease with the increase of the screening for these excitations. The influence of screening on linear polarization degrees of the 1P1 line is very small. The linear polarization degrees of aP1 line decrease sharply at low incident energy with the increase of the screening.  相似文献   

11.
类铍离子N3+激发态的能量、振子强度和跃迁几率   总被引:2,自引:1,他引:1  
利用多组态相互作用方法及Rayleigh-Ritz变分法,计算了类铍N3+ 基态(1s22s21S)和三个激发态(1s22s2p1P0, 1s22s2p3 P0, 1s22p23P)的能量,运用截断变分方法得到能量的改进量,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和辐射跃迁率.计算结果与其它理论和实验结果符合得很好.  相似文献   

12.
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。  相似文献   

13.
采用全相对论量子力学GRASP2程序,选取三电子组态1s22s22p, 1s22s2p2, 1s22p3,有限核费米模型,Breit和QED的高阶微扰修正,系统地研究了类硼等电子序列磁偶极M1 1s22s22p*"2P3/2-2P1/2( Z=10~100)光谱跃迁的精细能级结构间隔,跃迁概率和振子强度,计算结果表明1s22s2 2p和1s22p3组态之间存在明显的非动力学组态相关,采用三电子组态计算的精细能级结构间隔较单电子组态的计算结果有了显著的改善.  相似文献   

14.
盛勇  朱正和  易有根  蒋刚 《计算物理》2002,19(3):224-228
采用全相对论多组态Dirac-Fock方法,分别计算了类锂离子(Z=3-100)的磁偶跃迁1s^23s^2S1/2→1s^22s^2S1/2和电偶跃迁1s^2p^2P1/2→1s^22s^2S1/2的能级间隔,QED贡献和跃迁几率,比较了两者的参数与核电荷数Z的关系的差异,认为原子序数很大时,磁偶跃迁几率不能忽视。  相似文献   

15.
类磷离子精细结构能级和辐射寿命   总被引:1,自引:1,他引:0  
用全相对论多组态自洽场方法,计算了9个类磷离子的1s、2s、2p-、2p、3s、3p-、3p、3d-、3d、4s、4p-、4p、4d-、4d、4f-、4f、5s、5p-、5p、5d-、5d、5f-、5f、5g-、5g、6s、6p-、6p轨道的2309个精细结构能级和辐射寿命以及各种跃迁参数。能级的计算值和实验值符合得很好。同时,我们还发现了一些亚稳态能级。  相似文献   

16.
用全实加关联方法计算类锂离子(Z=11~20)偶极跃迁1s22s*"2S-1s23p*"2P1/2,3/2的跃迁能.非相对论能量用Rayleigh-Ritz变分法确定,相对论修正和质量极化效应用微扰论计算,还估算了来自量子电动力学效应的修正.得到的计算结果与现有的实验数据符合得很好,我们关于氯的类锂离子(Z=17)1s23p态的精细结构劈裂的计算结果揭示,相应的实验数据明显偏离等电子序列的物理规律.还算了1s22s-1s23p偶极跃迁的振子强度.  相似文献   

17.
采用基于全相对论框架的多组态Dirac-Fock方法,系统研究了类Be离子(Z=8-54)内壳层激发态1s2s22p的能量、辐射退激发和Auger退激发过程。详细讨论了电子关联效应对相关结构和退激发过程的影响。结果表明,来自于n=2和3壳层的电子关联效应最重要。另外,随着Z的增大,辐射退激发几率逐渐而平滑的增大,而Auger退激发几率的变化则不显著。本文计算结果与其它理论计算结果符合很好。  相似文献   

18.
用全相对论多组态自洽场方法,计算了类硅离子的1s、2s、2p-、2p 、3s、3p-、3p、3d-、3d、4s、4p-、4p、4d-、4d、4f-、4f、5s、5p-、5p、 5d-、5d、5f-、5f、5g-、5g、6s、6p-、6p轨道的912个精细结构能级和辐射寿命以及各种跃迁参数.能级的计算值和实验值符合得很好.从计算结果中发现了一些亚稳态能级.  相似文献   

19.
采用基于全相对论框架的多组态Dirac-Fock方法,系统研究了类Be离子(Z=8-54)内壳层激发态1s2s22p的能量、辐射退激发和Auger退激发过程.详细讨论了电子关联效应对相关结构和退激发过程的影响.结果表明,来自于n=2和3壳层的电子关联效应最重要.另外,随着Z的增大,辐射退激发几率逐渐而平滑的增大,而Auger退激发几率的变化则不显著.本文计算结果与其它理论计算结果符合很好.  相似文献   

20.
Mo XIV离子精细结构能级和辐射寿命   总被引:9,自引:0,他引:9  
用全相对论多组态自洽场方法 ,计算了类铜离子MoXIV的 1s ,2s ,2p- ,2p ,3s,3p- ,3p ,3d- ,3d ,4s,4p- ,4p ,4d- ,4d ,4f- ,4f,5s,5p- ,5p ,5d- ,5d ,5f- ,5f ,5g- ,5g ,6s,6p- ,6p ,6d- ,6d ,6f- ,6f,6g- ,6g ,6h- ,6h ,7s,7p- ,7p ,7d- ,7d ,7f- ,7f,7g- 和 7g轨道的 15 0 8个精细结构能级和辐射寿命以及其它各种跃迁参数 ,能级的计算值和实验值符合得很好 .另外还发现了一些寿命较长的能级. Energy levels, radiative lifetime and various transition parameters for allowed transitions among the 1 508 fine-structure levels belong to the (1s 22s 22p 63s 23p 6) 3d 104l, 3d 94l 2, 3d 105l, 3d 94l4m, 3d 106l, 3d 107l and so on configurations of the Cu-like ions Mo XIV have been calculated by using the expanded fully relativistic GRASP code. The results are compared with those available in the literature, and the accuracy of the present data is assessed. En...  相似文献   

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