Interstellar X-ray Absorption and Scattering

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.