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1.
 根据细致组态方法,采用不分辨的跃迁矩阵模型(UTA) 在组态平均近似下可以容易地计算由高功率激光产生的局域热动平衡状态下的等离子体的不透明度。 采用量子亏损理论计算在激光产生的中Z和高Z元素的等离子体中的高主量子数组态的UTA参数,可节省了大量的计算时间,采用全相对论处理的方法可以快速地计算任何高Z元素等离子体的不透明度。还可以很方便地确定最重要组态以及细致地分析跃迁矩阵。  相似文献   

2.
 报道计算高温高密等离子体吸收谱和发射谱(光学薄)的理论方法;该方法基于相对论原子理论,可以计算任何单元素以及多元素等离子体的谱分辨X射线吸收谱和发射谱(光学薄);应用了量子亏损理论,可以减少计算量。利用该方法计算金等离子体LTE吸收谱,计算结果与实验符合良好。本文还对金等离子体LTE的光学薄发射谱进行了研究, 这将有利于对实验进行进一步的诊断分析。该理论计算方法还可提供等离子体内各电离度能级布居等重要物理参数。因此经“标准实验”检验的该理论计算方法将是提供ICF“精密”物理辐射参数的重要基础。  相似文献   

3.
The transition energies, absorption oscillator strengths, line strengths and transition probabilities between computed levels are reported for the He-like to Ne-like Silicon ion sequences. Wavefunctions were determined relativistic configuration interaction (RCI) and multi-configuration Dirac-Fock (MCDF) technique included the Breit interaction, quantum electrodynamic (QED) corrections and nuclear mass corrections. The calculated values are in good agreement with the available experimental data and the recent theoretical values obtained from other methods. These data provide reference values for the level lifetimes, charge state distributions, and average charge of silicon plasmas.  相似文献   

4.
In this paper, we presented a method to calculate the spectral-resolved opacity for Non-Local-Thermodynamic-Equilibrium (non-LTE) plasmas. By solving the rate equations, we get the population. In the rate equations, configuration-averaged rate coefficients are used and the cross sections are calculated based on the first-perturbation theory. Using the detailed configuration accounting with the term structures treated by the unresolved transition array model, we calculated the spectral-resolved opacity of Al plasmas. The results are compared with those of other theoretical models. From the comparison, we can see that the present results fit well with other models for low-Z plasmas. For high-Z plasmas, we will give detailed discussion in the future.  相似文献   

5.
稠密、冷铝等离子体的辐射不透明度研究   总被引:1,自引:0,他引:1  
使用细致谱项模型、联合组态相互作用方法和R 矩阵方法计算了处于局域热动平衡条件下的稠密、冷铝等离子体的辐射不透明度 .组态相互作用方法用于获得束缚 束缚吸收截面所需要的偶极跃迁振子强度 ,R矩阵方法用于获得光电离截面 .对于温度在 6— 12eV、密度为 0 .36mg/cm3 的铝等离子体 ,计算得到的吸收系数在波长为 0 .35 1,0 .5 2 7和 1.0 5 4 μm处与实验结果符合较好 ,而温度在 3— 6eV时 ,理论计算比实验结果大. The radiative opacity has been investigated by using detailed term accounting approximation for dense, cold aluminum plasmas under local thermodynamic equilibrium. The configuration interaction scheme has been used to obtain the relevant atomic parameters for bound-bound absorption, such as excitation energies and oscillator strengths. R-matrix method has been used to obtain the photoionization cross sections. For aluminum plasmas of density 0.36 mg/cm 3, temperature of 6-12 eV, the...  相似文献   

6.
Multi-Configuration Dirac–Fock and relativistic configuration interaction calculations with the inclusion of the Breit interaction, quantum electrodynamics and finite nuclear mass corrections have been carried out in the extended optimal level (EOL) scheme on the transition wavelengths, transition probabilities, absorption oscillator strengths and line strengths of the Kα X-ray from Co XIIX to Co XXVI. The calculated values are compared with the other available data on He-like to Be-like cobalt and are found to be in very good agreement with them. This confirms the present calculations. These data provide reference values for level lifetimes, charge state distribution and average charge of cobalt plasmas.  相似文献   

7.
Detailed term and level accounting (DTA and DLA) schemes have been developed to calculate the spectrally resolved and Rosseland and Planck mean opacities of plasmas in local thermodynamic equilibrium. Various physical effects, such as configuration interaction effect (including core-valence electron correlations effect and relativistic effect), detailed line width effect (including the line saturation effect), etc., on the opacity of plasmas have been investigated in detail. Some of these physical effects are less capable or even impossible to be taken into account by statistical models such as unresolved transition arrays, super-transition-array or average atom models. Our detailed model can obtain accurate opacity of plasmas. Using this model, we have systematically investigated the radiative opacities of low, medium and high-Z plasmas under different conditions of temperature and density. For example, for aluminum plasma, in the X-ray region, we demonstrated the effects of autoionization resonance broadening on the opacity for the first time. Furthermore, the relativistic effects play an important role on the opacity as well. Our results are in good agreement with other theoretical ones although better agreement can be obtained after the effects of autoionization resonance broadening and relativity have been considered. Our results also show that the modelling of the opacity is very complicated, since too many physical effects influence the accuracy of opacity. For medium and high-Z plasmas, however, there are systematic discrepancies unexplained so far between the theoretical and experimental opacities. Here, the theoretical opacities are mainly obtained by statistical models. To clarify the discrepancies, efforts from both sides are needed. From the view-point of theory, however, a DLA method, in which various physical effects can be taken into account, should be useful in resolving the difference. Taking gold plasma as an example, we studied in detail the effects of core-valence electron correlation and line width on the opacity. Our DLA results correctly explained, for the first time, the relative intensity of the two strong absorption peaks located near the photon energy of 70 and 80 eV, which was experimentally observed by Eidmann et al. [Europhys. Lett., 1998, 44: 459].  相似文献   

8.
利用全相对论多组态Dirac-Fock方法系统地计算了高离化类铍离子的磁四极M2 2s21S0—2s2p3P2 (Z=10—103)自旋禁戒跃迁的能级间隔、跃迁概率和振子强度,计算中考虑了重要核的有限体积效应,Breit修正和QED修正,所得结果和最近的实验数据以及理论值进行了比较,结果表明:高原子序数的高电荷离子(Z≥70)磁四极M2自旋禁戒跃迁几乎可以和中性原子的光学允许跃迁相比拟,不仅在天体等离子体中,在ICF和MCF高温激光等离子体中,磁四极自旋禁戒跃迁和其他自旋禁戒跃迁(磁偶极、电四极)一样不容忽视,在双电子复合、不透明度、自由程等理论计算中应该考虑其影响. 关键词: 磁四极M2 能级间隔 跃迁概率 振子强度  相似文献   

9.
In this work, the multi-configuration Dirac-Fock (MCDF) and relativistic configuration interaction (RCI) methods have been used to calculate the transition wavelengths, electric dipole transition probabilities, line strengths and absorption oscillator strengths for the Kα X-ray from Mg III to Mg XI. We also take the contributions from the Breit interaction, finite nuclear mass corrections and quantum electrodynamics corrections to the initial and final levels, into account. The present values for Mg X and Mg XI were in good agreement with the previous experimental and theoretical results. The new data in this work provide reference values for the level lifetimes, charge state distributions, and average charge of magnesium plasmas.  相似文献   

10.
 利用全相对论性多组态Dirac-Fock平均能级方法系统地计算了高剥离类钠离子3s2S—3d2D(Z=14~103)电四极矩E2光谱跃迁的能级间隔,跃迁几率和振子强度,计算中考虑了核的有限体积效应,Breit修正和QED修正,所得结果和最近的实验数据及理论计算值进行了比较,计算结果表明:高原子序数的高荷电离子的电四极矩E2光谱跃迁的跃迁几率和中性原子的电偶极E1的相当,在ICF和MCF高温高密度激光等离子体中,电四极矩E2光谱跃迁过程不容被忽视。  相似文献   

11.
Calculations are reported of non-relativistic and relativistic oscillator strengths for the principal, sharp and diffuse series as well as some lifetimes in the spectra of singly-ionized silicon, germanium, tin and lead. The radial integrals were computed by employing the wave functions obtained from a semiempirical approach which included exchange effects (the semiempirical Xα method). Good agreement was obtained with available experimental and theoretical data. A comparison between non-relativistic and relativistic oscillator strengths confirms the importance of the spin-orbit interaction of the optical electron, as well as other relativistic effects for the oscillator strengths, even for the spectra of moderately heavy ions. Some systematic trends in the calculated oscillator strengths and line-strength ratios were investigated along the spectral series, as well as along the sequence of homologous ions.  相似文献   

12.
杨富利  易有根 《物理学报》2008,57(3):1622-1625
采用全相对论量子力学GRASP2程序,广义平均能级EAL模型,在核的有限体积效应,Breit和QED效应的高阶扰动基础上,考虑到原子实的极化,系统地计算了高剥离类钾离子4s 2S1/2─3d 2D3/2电四极矩E2光谱跃迁的能级间隔,跃迁概率和振子强度,结果表明:考虑原子实极化效应后,计算的精细能级结构间隔与实验数据之间的系统误差基本消除,其跃迁概率和振子强度属首次报道. 关键词: 高剥离态 能级间隔 振子强度  相似文献   

13.
应用不可分辨跃迁阵(UTA)模型结合相对论多组态Dirac-Fock方法,对金激光等离子体0.40~0.62nm范围内的带状谱和线状谱的主要特征参数进行了计算和分析,理论计算值和实验结果较之于单纯用UTA模型计算所得结果符合得更好。研究表明,对于谱线数目较少而又稀疏的跃迁,基于线谱的单独计算对UTA模型进行修正是合理和必要的。  相似文献   

14.
Using the fully relativistic configuration interaction (RCI) method and the multi-configuration Dirac-Fock (MCDF) method and taking quantum electrodynamical (QED) effect and Breit correction into account, wavelengths, transition probabilities and oscillator strengths were calculated for electric dipole (E1) transitions and magnetic dipole (M1) transitions in Au50+ ion. The obtained energy levels of some excited states and wavelengths of transitions in Au50+ ion from the method were compared with other theoretical and experimental results, and a good agreement with other results was shown. The calculated transition probabilities and oscillator strengths in E1 transitions using the velocity and length gauges respectively confirmed the accuracy of our calculations. The calculation results indicated that for high-Z highly ionized atom, some forbidden transitions could be very important.  相似文献   

15.
使用DTA(detailedtermaccounting)模型计算了温度为 5 6eV、密度为 0 .0 1g/cm3 的Mg等离子体的辐射不透明度以及Rosseland和Planck平均不透明度 .对于处于局域热动平衡 (LTE)下的Mg等离子体 ,利用Saha方程计算出各价离子的丰度 .MCHF方法得到Mg各价离子的能级以及束缚 束缚跃迁的振子强度 ,考虑了Doppler展宽和碰撞展宽 ,谱线线型采用Voigt线型 .束缚 自由以及自由 自由吸收截面使用AA模型得到. The spectral resolved opacity of high temperature Mg plasma at a temperature of 56 eV and a density of 0.01 g/cm 3 is calculated by the detailed term accounting (DTA) model. Saha equation is applied to obtain the population distribution of the plasma in local thermodynamic equilibrium. Atom levels and bound-bound absorption oscillator strengths are obtained from a multi-configuration Hartree-Fock (MCHF) calculation that includes Breit-Pauli relativistic correction. After ...  相似文献   

16.
Bao-Ling Shi 《中国物理 B》2022,31(5):53102-053102
Atomic data of highly charged ions (HCIs) offer an attractive means for plasma diagnostic and stars identification, and the investigations on atomic data are highly desirable. Herein, based on the fully relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) method, we have performed calculations of the fine-structure energy levels, wavelengths, transition rates, oscillator strengths, and line strengths for the lowest 21 states of 3p63d8-3p53d9 electric dipole (E1) transitions configurations in Fe-like ions (Z = 57, 60, 62, 64, 65). The correlation effects of valence-valence (VV) and core-valence (CV) electrons were systematically considered. In addition, we have taken into account transverse-photon (Breit) interaction and quantum electrodynamics (QED) corrections to treat accurately the atomic state wave functions in the final relativistic configuration interaction (RCI) calculations. Our calculated energy levels and transition wavelengths are in excellent agreement with the available experimental and theoretical results. Most importantly, we predicted some new transition parameters that have not yet been reported. These data would further provide critical insights into better analyzing the physical processes of various astrophysical plasmas.  相似文献   

17.
 使用R-矩阵方法和半经验方法,计算了高价离子Al-X 2s2 1S-2s2p1P0共振谱线在电子密度为1017cm-3时的线宽和线移随温度的变化关系,两种计算得到的线宽结果符合得比较好。使用半经验方法可以获得大量谱线的电子碰撞展宽,以满足需要大量数据的等离子体不透明度的计算的需要。使用半经验方法同时得到了其它一些谱线的电子碰撞宽度。  相似文献   

18.
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.  相似文献   

19.
Relativistic as well as non-relativistic oscillator strengths have been calculated for transitions in the principal sharp and diffuse series of P(III), As(III), Sb(III) and Bi(III) spectra. The radial integrals were computed by employing the wave functions obtained from a semiempirical method which included exchange effects. A comparison is presented for our calculated fik values with experimental and other theoretical data. The influence of relativistic effects on oscillator strengths for transitions in the P(III) through Bi(III) homologous sequence is discussed.  相似文献   

20.
激光金等离子体中Au47+、Au53+的离子结构和光谱分析   总被引:6,自引:1,他引:5  
根据扩展的相对论多组态狄拉克-福克(Dirac-Fock)理论,采用“多功能相对论原子结构程序(GRASP^2)”,考虑量子电动力学(QED)效应和布雷特(Breit)修正,选用二参量费米有限核电荷分布和扩展平均能级模型,并考虑组态问的相互作用和电偶极跃迁,计算了类锗Au^47+、类铁Au^53+的跃迁波长,跃迁几率和振子强度,计算的波长与实验值符合较好。研究表明,在类锗^47+、类铁Au^53+的跃迁中,3d-4f是一条较强的跃迁通道。计算所得的波长值对金等离子体的能级寿命、电荷态分布和平均电离度研究有一定的参考价值。  相似文献   

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