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arXiv · 2605.08981

Interstellar X-ray Absorption and Scattering

Linli Yan·Aigen Li·Fangjun Lu
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Abstract

Accurate estimates of the absorption of X-rays by interstellar gas and dust are of crucial importance for the analysis and interpretation of almost all astronomical soft X-ray observations. However, the present X-ray absorption data extensively used by the community were derived from a reduced interstellar abundance (~70% of solar) and ignoring dust scattering. Therefore, these X-ray absorption data, although highly popular, could have been substantially underestimated. Here we update the interstellar X-ray absorption and scattering by making use of updated atomic cross sections, updated interstellar abundances, and realistic X-ray dust physics, and appropriately distributing metal elements in gas and dust. The resulting X-ray absorption and scattering data are publicly available on GitHub.

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Linli Yan, Aigen Li, Fangjun Lu. 2026-05-09. Interstellar X-ray Absorption and Scattering. https://arxiv.org/abs/2605.08981

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