Weighted f-values, A-values, and line strengths for the E1 transitions among 3d, 3d4s, and 3d4p levels of Fe III

Weighted oscillator strengths, weighted radiative rates, and line strengths for all the E1 transitions between 285 fine-structure levels belonging to the 3d⁶, 3d⁵4s, and 3d⁵4p configurations of Fe III are presented, in ascending order of wavelength. Calculations have been undertaken using the general configuration interaction (CI) code CIV3. The large configuration set is constructed by allowing single and double replacements from any of 3d⁶, 3d⁵4s, 3d⁵4p, and 3d⁵4d configurations to nl orbitals with n?5,l?3 as well as 6p. Additional selective promotions from 3s and 3p subshells are also included in the CI expansions to incorporate the important correlation effects in the n=3 shell. Results of some strong transitions between levels of 3d⁶, 3d⁵4s, and 3d⁵4p configurations are also presented and compared with other available calculations. It is found that large disagreements occur in many transitions among the existing calculations.     

Electron collisions with Fe-peak elements: Forbidden transitions between the low lying valence states 3d, 3d4s, and 3d4p of Fe III

Effective collision strengths are presented for the Fe-peak element Fe III at electron temperatures (T_e in degrees Kelvin) in the range 2 × 10³ to 1 × 10⁶. Forbidden transitions results are given between the 3d⁶, 3d⁵4s, and the 3d⁵4p manifolds applicable to the modeling of laboratory and astrophysical plasmas.     

Collision strengths and line strengths for all transitions among the levels of the 1s22s22p, 1s22s2p2, and 1s22p3 configurations of boron-like ions

Collision strengths and electric-dipole line strengths have been calculated for all fine-structure transitions among the levels of the 1s²2s²2p, 1s²2s2p², and 1s²2p³ configurations in 17 boron-like ions with nuclear charge number Z in the range 10 ⩽ Z ⩽ 74. From these results the collision strengths and line strengths for transitions between energy terms and their analogs in jj coupling can also be obtained. The collision strength data cover impact-electron energies ⩽ 3.25Z²Ry or 44.2Z²eV. The effects of configuration mixing, parentage mixing, and intermediate coupling have been included in the calculations. The method used in calculating the collision strengths is a Coulomb-Born-Exchange method well suited for treating many members of an isoelectronic sequence simultaneously. The complete results have been given in terms of fits to simple functions of the impact-electron energy that are readily integrated over a Maxwellian distribution to obtain collision rates. Some discussion is given of important differences between the present method and the more usual Coulomb-Born-Exchange method, where it is assumed that the free electron sees the screened nuclear charge (Z - N).     

Breit-Pauli energy levels belonging to 2p, 2s2p, 2p, 2p3? configurations and all E1 transitions among these levels in Mg V

We present accurate oscillator strengths, line strengths and radiative rates for 1073 E1 transitions among the 86 levels belonging to 2s²2p⁴, 2s2p⁵, 2p⁶, and 2s²2p³(⁴S^o, ²D^o, ²P^o)3? configurations in Mg V. We have used 1s and 2s Hartree-Fock orbitals, re-optimized 2p on 2p³(²D^o)3s ³D^o and optimized 3s,3p,3d orbitals on real states. Sixteen additional orbitals up to 8d are optimized either as a correction to n = 3 physical orbitals or as a correlation orbital. A very large set of configurations including up to three electron promotions are used to account for all important correlation effects. All of the main five terms in the Breit-Pauli operator (except the orbit-orbit interaction) are included in order to account for the relativistic effects. Small adjustments to the diagonal elements of the Hamiltonian matrix are made to bring the calculated energies within a few cm⁻¹ of the corresponding NIST recommended data wherever available. The calculated oscillator strengths, line strengths, and radiative rates for almost all of the E1 transitions show excellent agreement with the corresponding MCDF results of Fischer. The recent results of Bhatia et al. are found to be consistently higher by 20-45%. The accuracy of the present calculation is considered to be better than the NIST accuracy ratings for various transitions.     

Energies and oscillator strengths for allowed transitions in S V,Cl VI and Fe XV

We present calculations using configuration interaction wave functions of energies and oscillator strengths for allowed transitions between states of the form 3l3l′ or 3l4l′ in S V, Cl VI and Fe XV. For the first two ions, LS coupling has been used throughout, but corrections incorporating experimental energies are made to the wave functions. For Fe XV, mass correction and Darwin terms are added to the Hamiltonian. These substantially improve the agreement between calculated and experimental energies. Some previously undetermined energy levels in Fe XV are predicted.     

Theoretical energy level spectra and transition data for 4p4d, 4p4d4f,and 4p4d configurations of W

The ab initio   quasirelativistic Hartree–Fock method developed specifically for the calculation of spectral parameters of heavy atoms and highly charged ions is used to derive transition data for a multicharged tungsten ion. The configuration interaction method is applied to include electron correlation effects. The relativistic effects are taken into account in the Breit–Pauli approximation for quasirelativistic Hartree–Fock radial orbitals. The energy level spectra, radiative lifetimes and Lande g$g$-factors are calculated for the 4p⁶4d², 4p⁶4d4f, and 4p⁵4d³ configurations of the ion W³⁶⁺. The transition wavelengths, spontaneous transition probabilities, oscillator strengths, and line strengths for the electric dipole, electric quadrupole, electric octupole, and magnetic dipole transitions among the levels of these configurations are tabulated.     

The energy levels and radiative transition probabilities for electric quadrupole and magnetic dipole transitions among the levels of the ground configuration, [Kr]4d4f, of W

Large-scale multiconfiguration Hartree-Fock and Dirac-Fock calculations have been performed for the ground configuration, [Kr]4d¹⁰4f⁴, energy levels of the W²⁴⁺ ion. The relativistic corrections were taken into account in the quasirelativistic Breit-Pauli and fully relativistic Breit (taking into account QED effects) approximations. The role of correlation, relativistic, and QED corrections is discussed. Line strengths, oscillator strengths, and transition probabilities in the Coulomb and Babushkin gauges are presented for the electric quadrupole (E2) transitions among these levels. The magnetic dipole transitions are also investigated. Dependence of the E2 transition probabilities on the gauge condition of the electromagnetic field potential is studied as well.     

Beam-foil study of 2p43s, 3p and 3d configurations in S VIII

The spectrum of seven times ionised sulphur, S VIII, has been observed from 450 to 1150 Å. About 30 lines have been identified as combinations between levels of the 2s²2p⁴3s, 3p and 3d configurations. The identifications are supported by isoelectronic comparisons along the FI isoelectronic sequence.     

Experimental values of transition probabilities for 2s22p3-2s2p4 transitions along the N I like sequence

Transition probabilities for the 2s²2p³²D/²P-2s2p⁴²P and 2s²2p³²D/²P-2s2p⁴²D transitions in O II, F III, Ne IV and Si VIII ions have been determined. The results are compared with atomic structure calculations. A good overall agreement with data based on the NCMET method is observed which underlines the importance of electron correlations for the investigated decay processes     

Theoretical energy level spectra and transition data for 4p4d, 4p4f and 4p4d configurations of W ion

The ab initio quasirelativistic Hartree-Fock method developed specifically for the calculation of spectral parameters of heavy atoms and highly charged ions was applied to determine atomic data for tungsten ions. The correlation effects were included by adopting the configuration interaction method. The Breit-Pauli approximation for quasirelativistic Hartree-Fock radial orbitals was employed to take into account relativistic effects. The energy level spectra, radiative lifetimes, Lande factors g were calculated for the 4p⁶4d, 4p⁶4f and 4p⁵4d² configurations of W³⁷⁺ ion. The atomic data, namely, the transition wavelengths, spontaneous emission rates and oscillator strengths for the electric dipole, electric quadrupole and magnetic dipole transitions among and within the levels of these configurations are tabulated.     

Analysis of the Ne- like 2p~53s,3p and3d configurations of Br XXVI

FollowingthefirstdemonstrationofsoftX-rayinNe-likeSe24 manyexperimentalandtheoreticalstudiesofthestructureofNe-likeionshavebeenreported.In1994NilsenandScofieldprovidedacriticalevaluationofthewavelengthsofallobserved3s-3plineswithlaserpropertiesforionsbetw…     

Pu在铁及铁氧化物上的吸附行为研究

为了解放射性核素在可能作为高放废物固化体包装容器材料及其腐蚀产物上的吸附行为,研究了包装容器材料的主要组分铁及铁的腐蚀产物FeO,Fe2O3,Fe3O4对Pu的吸附行为,探讨了水相pH值（1．0～10．0）,CO3^2-离子浓度（4．0 mmol/L～0．1mol/L）等因素对吸附的影响。实验结果表明,Pu在铁及其氧化物上的吸附能力随水相pH值增大而增大;实验环境中氧浓度变化对Pu在铁及其氧化物上的吸附影响较小;CO3^2-浓度增大不利于Pu的吸附。     

Calculated wavelengths,oscillator strengths,and energy levels for n = 2−2 and 2–3 transitions in F-like ions Mg IV to Ni XX and for 3−3 and other transitions in Mg IV,Al V,and Si VI

Weighted oscillator strengths, energy levels, and wavelengths are calculated for the 2s²2p⁵-2s2p⁶, 2s²2p⁵-2²2p⁴3s, and 2s²2p⁵-2s²2p⁴3d transition arrays for F-like ions in the isoelectronic sequence from Mg IV to Ni XX and in addition for n = 3?3 and other transitions in Mg IV, Al V, and Si VI. The calculation involves the computation of ab initio values of Slater radial energy integrals using a Hartree-Fock-Relativistic computer program package, which includes configuration-interaction and applies the Blume-Watson method for spin-orbit integrals. Some of the parameters are subsequently optimized on the basis of empirical data. Adopted values are tabulated along with atomic energy level compositions.     

99Tc在Fe,Fe2O3和Fe3O4上的吸附行为研究

用批式法研究了大气条件下99Tc在Fe,Fe2O3和Fe3O4上的吸附行为,考察了吸附平衡后溶液中99Tc的存在价态.实验结果表明随着溶液pH值(5～12)、CO2-3浓度(1×10-8～1×10-2 mol/L)的增大,99Tc在Fe上的吸附比减小;溶液pH值、CO2-3浓度的变化基本不影响99Tc在Fe2O3和Fe3O4上的吸附;99Tc在这3种吸附材料上的吸附行为均可用Freundlich吸附等温式表示;当Fe作吸附材料时,吸附平衡后99Tc主要以Tc(Ⅳ)的形式被吸附,当Fe2O3和Fe3O4作为吸附材料时,99Tc主要以Tc(Ⅶ)的形式被吸附.     

Collision strengths for innershell excitation of Li-like ions from the 1s22s and 1s22p levels to the 1s2l3l′ levels

Collision strengths, collision rates, transition energies, and electric-dipole radiative line strengths have been calculated for innershell excitation from the 1s²2s and 1s²2p levels to all levels of the 1s2l3l′ configurations in Li-like ions with nuclear charge number Z in the range 6 ? Z ? 74. The collision strengths, which are obtained using a Coulomb-Born-exchange method, are expressed in a convenient form in terms of the scaled hydrogenic ion collision strengths $\text{Z}{}^2\text{Ω}{}_{\mathrm{<mtext>H</mtext>}}$ and $\text{Z}{}^2\text{Ω}{}_{\mathrm{H}}{}^{\mathrm{e}}$. Results for innershell excitation to the levels of the 1s2l2l′ configurations considered in earlier work are also expressed in this form. The calculations include configuration mixing, parentage mixing, and intermediate coupling effects.     

Proton excitation rate coefficients and cross sections among the fine-structure levels of the (2s2p)3P state in Be-like ions

Proton excitation cross sections and rate coefficients are given for the fine-structure transitions in the (2s2p)³P state in the Be-like ions C III, N IV, O V, F VI, Ne VII, Mg IX, Si XI, S XIII, Ar XV, Ca XVII, and Fe XXIII. In the low-energy region we used the semiclassical Coulomb excitation method, while for the intermediate-energy range, we used a close-coupling impact parameter method. For the temperatures tabulated here, the rate coefficients for all the transitions are better than 5%.     

Resolution enhancement of the 3He(d,p)4He resonance for profiling helium in solids

The use of nuclear resonances techniques for characterizing the distribution and lattice location of implanted atoms in metals is a direct and, in principle, simple method for studying helium and hydrogen gas in CTR first wall materials. However, the reaction ³He(d,p)⁴He, has a broad (350 keV) half-width in the resonance yield curve. When using a deuteron beam, under normal probing conditions, to measure helium distributions in metals, a rather low stopping power results in limited resolution of about 3 μm. In many cases resolution of a few thousand angstroms or better is necessary. We have experimentally examined two resolution enhancement methods and reported the results in a previous article. The present paper will review those results and examine limitations of resolution enhancement that are obtainable through geometrical and mathematical techniques.     

Calculated wavelengths,oscillator strengths,and energy levels for allowed n = 2–3 transitions in Be-like ions O V to Ni XXV

Calculated weighted oscillator strengths (O V to Ni XXV), wavelengths (Mg IX to Ni XXV), and energy levels (S XIII to Ni XXV) are listed for n = 2–3 transitions in ions belonging to the Be-like isoelectronic sequence along with available measured wavelengths (Mg IX to Ni XXV). They were computed with the aid of a Hartree-Fock-Relativistic computer program package which employs the Blume-Watson method for spin-orbit integrals. Configuration interaction was taken into account between the 2s², 2p², 2s3s, 2s3d, and 2p3p even configurations and the 2s2p, 2s3p, 2p3s, and 2p3d odd configurations. Ab initio values of Slater radial energy integrals were adjusted on the basis ofempirical data.     

Fusion Cross Section of $${\mathrm{T(d,n)}}^{4}{\mathrm{He}}$$ and $${}^{3}{\mathrm{He(d,p)}}^{4}{\mathrm{He}}$$3He(d,p)4He Reactions by Four Parameters Formula

Fusion cross sections of light nuclei are calculated by a complex potential and taking into account of conservation of angular momentum and parity. The nuclear potential is assumed to be as simple as a spherical complex square well with a rigid core. Then the nuclear phase shift is extracted from continuity condition of inverse of the logarithmic derivative of the wave functions as a complex quantity. The quantum tunneling probability and cross section are obtained via real and complex components of nuclear phase shift. The obtained results for the two most important light nuclei reactions, \({\mathrm{T(d,n)}}^{4}{\mathrm{He}}\), \({}^{3}{\mathrm{He(d,p)}}^{4}{\mathrm{He}}\) are compared with other theoretical formulas and experimental data. Despite that the theory is simplified as much as possible and the complexities and details of nuclear interactions has been ignored, excellent agreements with experimental data are achieved.     

Transition probabilities for 5s-5p, 5p-5d, 4f-5d, and 5d-5f transitions in Ag-like ions with Z = 50-86

The wavelengths, electric dipole transition probabilities, and oscillator strengths are calculated for transitions between low-lying states (5s-5p, 5p-5d, 4f-5d, and 5d-5f) in the silver isoelectronic sequence (50 ? Z ? 86) using relativistic perturbation theory with a zero-approximation model potential. The results are compared with the corresponding data of the relativistic Hartree-Fock theory and the relativistic many-body perturbation theory. The results of these three theoretical approaches are compared with available experimental data for the level lifetimes. Possible reasons for some disagreements are discussed.