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arXiv · 2210.13427

R-matrix electron-impact excitation data for the H- and He-like ions with Z=6-30

Junjie Mao·G. Del Zanna·Liyi Gu·Chunyu Zhang·N. R. Badnell
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Abstract

Plasma models built on extensive atomic data are essential to interpreting the observed cosmic spectra. H-like Lyman series and He-like triplets observable in the X-ray band are powerful diagnostic lines to measure the physical properties of various types of astrophysical plasmas. Electron-impact excitation is a fundamental atomic process for the formation of H-like and He-like key diagnostic lines. Electron-impact excitation data adopted by the widely used plasma codes (AtomDB, CHIANTI, and SPEX) do not necessarily agree with each other. Here we present a systematic calculation of electron-impact excitation data of H-like and He-like ions with the atomic number Z=6-30 (i.e., C to Zn). Radiation damped R-matrix intermediate coupling frame transformation calculation was performed for each ion with configurations up to $n=6$. We compare the present work with the above three plasma codes and literature to assess the quality of the new data, which are relevant for current and future high-resolution X-ray spectrometers.

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Junjie Mao, G. Del Zanna, Liyi Gu, Chunyu Zhang, N. R. Badnell. 2022-10-20. R-matrix electron-impact excitation data for the H- and He-like ions with Z=6-30. https://doi.org/10.3847/1538-4365%2Fac9c57

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