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X-ray powerful diagnostics for highly-ionized plasmas: He-like ions

D. Porquet·R. Mewe·J. S. Kaastra·J. Dubau·A. J. J. Raassen
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Abstract

The calculations of the ratios of the Helium-like ion X-ray lines from C V to Si XIII are revisited in order to apply the results to density, temperature and ionization process diagnostics of data from high-resolution spectroscopy of the new generation of X-ray satellites: Chandra and XMM-Newton. Comparing to earlier computations, Porquet & Dubau (2000), the best experimental values are used for radiative transition probabilities. The influence of an external radiation field (photo-excitation), the contribution from unresolved dielectronic satellite lines and the optical depth are taken into account. These diagnostics could be applied to collision-dominated plasmas (e.g., stellar coronae), photo-ionized plasmas (e.g., ``Warm Absorber'' in AGNs), and transient plasmas (e.g., SNRs).

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D. Porquet, R. Mewe, J. S. Kaastra, J. Dubau, A. J. J. Raassen. 2002-04-08. X-ray powerful diagnostics for highly-ionized plasmas: He-like ions. https://arxiv.org/abs/astro-ph/0204119

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