Wavelengths, transition probabilities, and oscillator strengths for M-shell transitions in tungsten ions with partially filled 3p subshell

Abstract

Wavelengths, transition probabilities, and oscillator strengths have been calculated for M-shell electric dipole (E1) transitions in Al-like W61+ through Cl-like W57+, with partially filled 3p subshell. The fully relativistic multiconfiguration Dirac–Fock (MCDF) method, taking quantum electrodynamical effect and Breit correction into account, was used in the calculations. Calculated energy levels of M-shell excited states in Al-like through Cl-like W ions from the method were compared with some available theoretical and experimental results, and good agreement with them was achieved.

Benchmarking calculations with spectroscopic accuracy of excitation energies and wavelengths in sulfur-like tungsten

“…The differences between the previous calculations of atomic energy levels [8,9] and the NIST measured value are several times or one order of magnitude larger than the corresponding differences calculated for the present theoretical MCDHF/RCI energies. This indicates that the present theoretical excitation energies of S-like W are highly accurate and represent a great improvement on the latest theoretical results [8,9]. In addition, excitation energies in Table III are presented in the order of the present theoretical excitation energies.…”

“…On average, CV electron correlation plays a smaller role than VV electron correlation, as expected for transitions involving valence excitations. CV electron correlation was systematically omitted in all previous theoretical calculations performed for S-like W [8,9,11,24]. However, limiting electron correlation to VV electron correlation is not enough to reach the needed accuracy for assisting spectroscopists in the spectral lines identification process, as discussed in Ref.…”

“…Excitation energies of S-like W from the present MCDHF/RCI calculations, as well as the compiled data from the NIST ASD [14], are listed in Table III. For comparison, the two theoretical data sets reported by Aggarwal et al [8], and the theoretical results provided by Xu et al [9] are also included in the table.…”

“…These applications stimulated some calculations of excitation energies and wavelengths for S-like W [8][9][10][11]. However, a satisfactory accuracy has not been achieved yet.…”

“…For example, the two data sets reported by Aggarwal et al [8], using the general-purpose relativistic atomic structure package (GRASP89) [12] and the flexible atomic code (FAC) [13], are inconsistent, with excitation energy deviations of up to 30 000 cm −1 . The excitation energies calculated by Xu et al [9] differ by 3 000 − 70 000 cm −1 from the results of Ref. [8], although both sets are evaluated using the same GRASP89 code [12].…”