On the Absorption of X-rays in the Interstellar Medium
نویسنده
چکیده
We present an improved model for the absorption of X-rays in the interstellar medium (ISM) intended for use with data from future X-ray missions with larger effective areas and increased energy resolution such as Chandra and the X-ray Multiple Mirror mission, in the energy range & 100 eV. Compared to previous work, our formalism includes recent updates to the photoionization cross section and revised abundances of the interstellar medium, as well as a treatment of interstellar grains and the H2 molecule. We review the theoretical and observational motivations behind these updates and provide a subroutine for the X-ray spectral analysis program XSPEC that incorporates our model. Subject headings: Atomic data — ISM: abundances — dust, extinction — X-rays: ISM
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