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arXiv · 2107.14088

Cloudy in the microcalorimeter era: improved energies for Si and S K$\alpha$ fluorescence lines

Francesco Camilloni·Stefano Bianchi·Roberta Amato·Gary Ferland·Victoria Grinberg
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Abstract

The upcoming X-ray missions based on the microcalorimeter technology require exquisite precision in spectral simulation codes in order to match the unprecedented spectral resolution. In this work, we improve the fluorescence K$\alpha$ energies for Si II-XI and S II-XIII in the code Cloudy. In particular, we provide here a patch to update the Cloudy fluorescence energy table, originally based on Kaastra & Mewe (1993), with the laboratory energies measured by Hell et al. (2016). The new Cloudy simulations were used to model the Chandra/HETG spectra of the High Mass X-ray Binary Vela X-1 previously presented in Amato et al. (2021), showing a remarkable agreement and a dramatic improvement with respect to the current release version of Cloudy (C17.02).

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Francesco Camilloni, Stefano Bianchi, Roberta Amato, Gary Ferland, Victoria Grinberg. 2021-07-05. Cloudy in the microcalorimeter era: improved energies for Si and S K$\alpha$ fluorescence lines. https://doi.org/10.3847/2515-5172%2Fac0cff

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