类氦等电子系列离子n~(1,3)S和n~(1,3)P态统一的半经验能量计算公式

本文给出了类氦等电子系列离子n~(1,8)S和n~(1,3)P态统一的半经验能量计算公式,此公式是通过拟合Ermold6v和Jones关于类氦离子2≤Z≤42最低谱项(n=2—5)的计算值得到的。根据本文提供的公式,可以予言任何n~(1,3)S和n~(1,3)P高激发态能级值及相应能级之间跃迁的波长值,对一些ls~2一lsnp跃迁波长将本文的计算值与实验值进行了比较,结果表明除个别外在实验误差范围内两者十分吻合,此外还对类氦等电子系列离子量子数亏损的规律性进行了详细的讨论。     

CoⅩⅧ离子2s~22p~53l2s2p~63l、2s~22p~54l组态的能级及跃迁波长计算

本文用相对论多组态Dirac-Fock广义平均能级(MCDF-EAL)模型,计算了可能形成超真空紫外区相干辐射的类氖等离子体激光工作物质的CoXVⅢ离子2s~22p~53l、2s2p~63l、2s~22p~54l组态精细结构能级的能量值,以及3l、4l-2p~6(~1S_0)、3l-3l＇、3l-4l＇、4l-4l＇多重态之间的跃迁波长值。3l、4l-2p~6(~1S_0)跃迁波长计算值与已知观测值符合相当好。     

25≤Z≤35类氟离子能级和相干辐射波长的MCDF计算

本文用相对论多组态Dirac-Fock广义平均能级(MCDF-EAL)模型,计算了可形成软x射线区相干辐射的可能的类氟等离子体型激光工作物质:25≤Z≤35的类氟离子2s~22p~5、2s~22p~43l、2s2p~53l、2p~63l组态共113条能级,以及上述单激发态M亚壳层至2s~22p~5态的~2P_(3/2)、~2P_(1/2)和2s2p~6态的~2S_(1/2)能级全部允许跃迁的强相干辐射波长值。从上述的波长理论计算值与实验观测值对比,可知我们的计算结果是相当可靠的。     

溴到铷的类钠离子能级辐射跃迂几率和能级寿命

本文在多组态Dirac-Fock(MCDF)理论框架下计算了水窗波段(λ:23.3～43.8A,相当于Z:34～46)的溴到铷的类钠离子1s~22s~22p~6nlj(n=3～15,l=0～6)各能级能量及各能级n_il_ij_i—n_kl_kj_k(n_i≤6,n_h≤15)间的电偶极辐射跃迁几率,并由此得出可能产生软X射线激光跃迁(4f-5g,4d-5f,4f-6g,4d-6f)的激光上能级的寿命,把计算得到的跃迁波长与实验测量值进行比较,其相对误差小于0.35％。     

KrVI离子能级和振子强度的理论计算

利用组态相互作用理论和参数外推法,计算了KrVI离子4s~24p—4s4p~2、4s~24p—4s~24d和4s4p~2—4p~3跃迁的能级、谱线波长和振子强度。与已有实验结果比较表明:波长的理论计算值与观测值在0.7A内很好符合,振子强度的理论计算值较大的跃迁均是实验中观测到的跃迁。     

类氢离子Mg~(11 ),Al~(12 )光谱参数的理论计算及在温度诊断中的应用

采用“多功能相对论原子结构计算程序”GRASP2 (1 992 ) ,分别计算了类氢离子 Mg11 ,Al12 能级之间电偶跃迁 (E1 )的波长、几率和振子强度 ,其中跃迁波长值与实验值相吻合。充分利用计算结果 ,采用等电子线率法对文献 [4 ]的谱线强度比测温实验进行理论上的探讨 ,即利用原子序数相差不大 (ΔZ=1 ,2 )的两种示踪原子相同离化态的同种跃迁谱线进行电子温度诊断 ,以期望提高测温精度     

BrV离子4p^3—4s4P^2跃迁的能级和振子强度

利用组态相互作用理论和参数外推方法,计算了BrV离子4p~3 4s4p~2跃迁的能级、谱线波长和电偶极跃迁的振子强度。4s4p组态的能级计算值与已有数据很符合,4p~3组态的能级以及4p~3-4s4p~2跃迁的谱线波长和振子强度纯属预言值。     

铜到钼的类钠离子能级结构及软X射线光谱理论计算

本文采用Hartree-Fock自洽场方法,从理论上计算了铜到钼的类钠离子1s~22s~22p~6nl(n=3～6,l=O～5)各能级能量。给出了有可能实现软X射线激光的跃迁(5g—4f,5f—4d,6g—4f,6f—4d)的光谱性质:跃迁波长、振子强度,并和实验值进行了比较,跃迁波长的相对误差不超过千分之二。从计算结果可知,Se的6f—4d跃迁,Br的6g—4f跃迁,Zr的5f—4l跃迁,Nb的5g—4f跃迁都已进入水窗波段。     

类锂硅离子能级结构及软X射线激光光谱理论计算

本文采用Hartree-Fock自洽场方法,从理论上计算出类锂硅离子1s~2nl(n=2～7,l=0～5)各能级能量,并给出在极紫外(波长小于400(?))范围内各跃迁谱线的光谱性质、波长、振子强度和跃迁几率.对实验中已实现软X射线激光的跃迁(5d-3p,5f-3d,6d-3p,6f-3d),计算所得的跃迁波长与实验值完全相符.与现有文献的波长比较,相对误差不超过1%.     

高离化Kr~(33+)离子2~2P-n~2S(2≤n≤9)的偶极跃迁行为（英文）

本文构造了高离化Kr~(33+)离子1s~2ns(2≤n≤9)和1s22p态的波函数并利用其计算了体系的非相对论能量.为了得到高精度的理论计算结果,将相对论修正和质量极化效应作为一级微扰计算了体系的总能量和2~2P-n~2S(2≤n≤9)跃迁能,本文的结果与有限的实验数据符合的较好.在此基础上完成了2~2Pn~2S(2≤n≤9)偶极跃迁三种规范下振子强度的理论计算,三者的一致性进一步证明所构造的波函数在整个空间的准确性和可靠性.     

Dipole Polarizabilities of the Ground States for Berylliumlike Ions

Dipole polarizabilities of the ground states for berylliumlike ions with nuclear charge Z = 4 to 10 are calculated by using the Rayleigh-Ritz variational method with multiconfiguration interaction wave functions. The representative models of convergence are listed and compared with other theoretical data for nuclear charge Z = 4 to 6. The present dipole polarizabilities are in good agreement with previous accurate theoretical values available in the literature. For results with greater nuclear charge number, the present calculations may provide benchmarked data for future theoretical and experimental studies. Dynamic dipole polarizabilities of the ground state for the beryllium atom at selected frequencies are also calculated and compared with other theoretical values in the literature.     

表面氧钝化碳化硅纳米团簇电子结构和光学性质的第一性原理研究

基于密度泛函理论(DFT)和广义梯度近似(GGA),对氧钝化条件下4H-SiC纳米团簇的电子结构和光学性质进行了研究。计算了不同直径的4H-SiC纳米球氧钝化后的能带结构、电子态密度和光学性质。团簇的尺度在0.4~0.9 nm之间,构建表面仅存在硅氧双键和表面仅存在碳氧双键的两种模型。研究表明硅氧双键和碳氧双键所引起的缺陷态位于原4H-SiC的价带和导带之间,并且缺陷态与价带顶的能量差随纳米团簇颗粒直径的增大而减小;缺陷态主要是由Si原子外层电子和氧原子外层电子轨道杂化引起的。同时,由于氧的存在,对碳化硅的结构产生一定的影响,这也是缺陷态形成的一个原因。另外,碳氧双键和硅氧双键钝化对4H-SiC纳米团簇的光学性质有着不同的影响。在表面仅存在C=O的情况下,4H-SiC纳米团簇表现出各向同性的性质。在表面仅存在Si=O的情况下,4H-SiC纳米团簇表现出各向异性的性质。     

boldmath Multi-configuration Dirac-Hartree-Fock (MCDHF) calculations for Zn-like sequence from Z=48 to 54

The 4s4p excitation energies and the 4s²-4s4p E1 transitions for zinc-like ions from Z=48 to 54 are calculated by the multi-configuration Dirac-Hartree-Fock (MCDHF) method in this paper. The results for fine-structure energy levels, wavelengths and lifetimes between Z=48 (Cd) and Z=54 (Xe) are presented and compared with other theoretical and experimental results. The calculated values including core-valence correlation are found to be very similar to other theoretical and experimental values. We believe that our calculated values can guide experimentalists in identifying the fine-structure levels in their future work.     

Effects of valence-valence,core-valence and core-core correlations on the fine-structure energy levels in Zn-like ions

We report on large ab initio calculation for the 4s²4s^2–4s4p transitions in the Zinc-like sequence, using the multi-configuration Dirac-Hartree-Fock method. Results for fine-structure energy levels, the wavelengths, transition rates and lifetimes between Z = 70 (Yb) and Z= 92 (U) are presented and compared with other theories and experiments. The calculated values including core-valence correlation are found to be similar and to compare very well with other theories and experiments values. We believe that our extensive calculated values can guide experimentalists in identifying the fine-structure levels in their future work.     

类锂V^20＋—Cu^26＋离子的谱线波长和振子强度

用多组态ＨＸＲ方法计算了类Ｌｉ离子Ｖ２０＋－Ｃｕ２６＋１ｓ２ｎｌ（ｎ＝２～６，ｌ＝０～４）组态能级之间的电偶极跃迁波长和振子强度，并和已有的实验结果进行了比较。     

Calculations of particle and heavy ion interactions with space shielding materials using the SHIELD-HIT transport code

Spectra of secondary particles produced by nucleus–nucleus interactions and heavy-ion interactions in the extended targets of interest for space research were calculated using the Monte Carlo code SHIELD-HIT. This code simulates the interactions of hadrons and atomic nuclei of arbitrary charge and mass number (Z,A) with complex extended targets in a wide energy range, from 10 GeV/u down to 1 MeV/u, and to thermal energies in the case of neutrons. Inelastic nuclear reactions in SHIELD-HIT are simulated using the Russian models of nuclear reactions. The total reaction cross sections evaluated by these models are discussed for proton and carbon interactions with different nuclei in a wide energy range. Production of secondary neutrons and charged secondary particles from the thick targets of lead, water and PMMA irradiated by ⁴He, ¹²C and ²⁸Si ions of different energies was calculated and compared with the experimental data. The results obtained by SHIELD-HIT are in reasonable agreement with experiments and are promising for further applications in space research.     

Multiconfiguration Dirac–Fock calculations of Zn K-shell radiative and nonradiative transitions

Zinc K-shell radiative and radiationless transition rates are calculated using the multiconfiguration Dirac–Fock method. Correlation up to the 4p orbital is included in almost all transition rate calculations. Calculated radiative transition rates and transition probabilities are compared with Scofield's Dirac–Hartree–Slater and Dirac–Hartree–Fock calculations, presenting good agreement with the later. Radiative transition intensity ratios involving the strongest lines are compared with theoretical, experimental, and empirical-fit values. Most ratios are in close agreement with the empirical-fit values from NIST's Fundamental Parameters database. Calculated radiationless transition rates and ratios are compared with Chen et al.'s Dirac–Fock values and Safronova et al.'s Dirac–Fock values. The K-LL transition rates are overall lower than Chen et al.'s values, whereas the K-LX and K-XY transition rates are overall higher. Calculated K-LX/K-LL and K-XY/K-LL ratios are relatively close to the experimental values compared. Some calculated intensities relative to K-L are in good agreement with the experimental values, whereas others present worse agreement. The calculated fluorescence yield is higher than all theoretical, experimental, and empirical-fitted values compared, probably because the total radiationless transition rate value calculated in the present work is relatively low.     

Propagation dynamics of optical vortices in Laguerre–Gaussian beams

We have calculated the propagation dynamics of an initial off-axis vortex with topological charge 1 in Laguerre–Gaussian background beams , which are examples of background beams with non-generic dislocation surfaces, on which the real and imaginary parts of the light field are zero. When initially a vortex with broad core (e.g., r-vortex) is embedded in the background beam, the dislocation surfaces are destroyed during propagation and two vortices with opposite charge are created per dislocation surface in planes perpendicular to the propagation direction. For a vortex with narrow core (e.g., point vortex) diffraction is important and leads to the birth of more than two vortices per dislocation surface. These results are also valid for other background beams with dislocation surfaces, e.g., Hermite–Gaussian and Ince–Gaussian beams. We investigated experimentally the spatial evolution of the intensity distribution of an initial off-axis vortex with narrow core and topological charge 1 in background beams. The experimental results are in good agreement with the calculated intensity distributions.     

高离化类铜离子4s—4p跃迁的理论计算与量子电动力学效应

采用相对论多组态从头计算方法，系统计算了高离化类铜离子等电子序列Ｉｎ２０－Ｕ６３＋（Ｚ＝４９～９２）４ｓ－４ｐ跃迁波长和能级间隔，计算结果与文献的实验值和计算值作了比较。结果表明，在高离化类铜离子体系中存在更显著的量子电子动力学效应。     

Search for correlation effects in theM 4, 5 N 4, 5 N 4, 5 Auger spectrum of xenon

TheM _{4, 5} N _{4, 5} N _{4, 5} Auger spectrum of xenon has been measured with high resolution. Theoretical line intensities and relative line energies for this spectrum have been calculated applyingjj coupling to the initial states and intermediate coupling and configuration interaction to the final states. Two facts indicate that correlation effects are only small in the present case: The application of configuration interaction gives only small changes in line intensities and the experimental line intensities are found to be in good agreement with theoretical results, calculated without configuration interaction.