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arXiv · 2504.05286

UK APAP R-matrix electron-impact excitation cross-sections for modelling laboratory and astrophysical plasma

G. Del Zanna·G. Liang·J. Mao·N. R. Badnell
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Abstract

Systematic R-matrix calculations of electron-impact excitation for ions of astrophysical interest have been performed since 2007 for many iso-electronic sequences as part of the UK Atomic Process for Astrophysical Plasma (APAP) network. Rate coefficients for Maxwellian electron distributions have been provided and used extensively in the literature and many databases for astrophysics. Here, we provide averaged collision strengths to be used to model plasma where electrons are non-Maxwellian, which often occur in laboratory and astrophysical plasma. We also provide for many ions new Maxwellian-averaged collision strengths which include important corrections to the published values. The H- and He-like atomic data were recently made available in Mao+(2022). Here, we provide data for ions of the Li-, Be-, B-, C-, N-, O-, Ne-, Na-, and Mg-like sequences.

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G. Del Zanna, G. Liang, J. Mao, N. R. Badnell. 2025-04-07. UK APAP R-matrix electron-impact excitation cross-sections for modelling laboratory and astrophysical plasma. https://arxiv.org/abs/2504.05286

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