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arXiv · 2412.01606

Cloudy and the High-Resolution Microcalorimeter Revolution: Optical, UV, and X-ray Spectra of One-electron Systems

Chamani M. Gunasekera·Peter A. M. van Hoof·Marios Chatzikos·Gary J. Ferland
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Abstract

With the launch of the XRISM microcalorimeter mission, space-based X-ray observations will achieve a record spectral resolving power of $R\equiv E/\Delta E\sim$1200. With this resolving power, emission features associated with fine-structure energy levels of some species will be resolved, sometimes for the first time. The plasma code, Cloudy, was not originally designed for high-resolution X-ray spectroscopy and throughout its history did not resolve fine-structure components of Lyman lines. Here we expand Cloudy to resolve these fine-structure energy levels and obtain predicted X-ray spectra that match the resolution of new microcalorimeter observations. We show how the Lyman lines can be used as column density indicators in the hot X-ray emitting gas in a cluster of galaxies such as Perseus, and examine their sensitivity to external radiation fields and turbulence.

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Chamani M. Gunasekera, Peter A. M. van Hoof, Marios Chatzikos, Gary J. Ferland. 2024-12-02. Cloudy and the High-Resolution Microcalorimeter Revolution: Optical, UV, and X-ray Spectra of One-electron Systems. https://arxiv.org/abs/2412.01606

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