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arXiv · 2408.02734

Argon X-ray absorption in the local ISM

E. Gatuzz·T. W. Gorczyca·M. F. Hasoglu·J. A. García·T. R. Kallman
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Abstract

We present the first comprehensive analysis of the argon K-edge absorption region (3.1-4.2 \AA) using high-resolution HETGS {\it Chandra} spectra of 33 low-mas X-ray binaries. Utilizing R-matrix theory, we computed new K photoabsorption cross-sections for {\rm Ar}~{\sc i}--{\rm Ar}~{\sc xvi} species. For each X-ray source, we estimated column densities for the {\rm Ar}~{\sc i}, {\rm Ar}~{\sc ii}, {\rm Ar}~{\sc iii}, {\rm Ar}~{\sc xvi}, {\rm Ar}~{\sc xvii} and {\rm Ar}~{\sc xviii} ions, which trace the neutral, warm and hot components of the gaseous Galactic interstellar medium. We examined their distribution as a function of Galactic latitude, longitude, and distances to the sources. However, no significant correlations were discerned among distances, Galactic latitude, or longitude. Future X-ray observatories will allow us to benchmark the atomic data as the main resonance lines will be resolved.

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E. Gatuzz, T. W. Gorczyca, M. F. Hasoglu, J. A. García, T. R. Kallman. 2024-08-05. Argon X-ray absorption in the local ISM. https://doi.org/10.1051/0004-6361/202450539

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