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arXiv · 2101.11193

Visible spectra of W8+ in an electron-beam ion trap

Q. Lu·C. L. Yan·J. Meng·G. Q. Xu·Y. Yang·C. Y. Chen·J. Xiao·J. G. Li·J. G. Wang·Y. Zou
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Abstract

To provide spectroscopic data for lowly charged tungsten ions relevant to fusion research, this work focuses on the W8+ ion. Six visible spectra lines in the range of 420-660 nm are observed with a compact electron-beam ion trap in Shanghai. These lines are assigned to W8+ based on their intensity variations as increasing electron-beam energy and the M1 line from the ground configuration in W7+. Furthermore, transition energies are calculated for the 30 lowest levels of the 4f14 5s2 5p4, 4f13 5s2 5p5 and 4f12 5s2 5p6 configurations of W8+ by using the flexible atomic code (FAC) and GRASP package, respectively. Reasonably good agreement is found between our two independent atomic-structure calculations. The resulting atomic parameters are adopted to simulate the spectra based on the collisional-radiative model implemented in the FAC code. This assists us with identification of six strong M1 transitions in 4f13 5s2 5p5 and 4f12 5s2 5p6 configurations from our experiments

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Q. Lu, C. L. Yan, J. Meng, G. Q. Xu, Y. Yang, C. Y. Chen, J. Xiao, J. G. Li, J. G. Wang, Y. Zou. 2021-01-27. Visible spectra of W8+ in an electron-beam ion trap. https://doi.org/10.1103/physreva.103.022808

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