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arXiv · 2411.15357

New Insights with XRISM & Cloudy: A novel Column Density Diagnostic

Chamani M. Gunasekera·Peter A. M. van Hoof·Masahiro Tsujimoto·Gary J. Ferland
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Abstract

We present a simple, yet powerful column density diagnostic for plasmas enabled by X-ray microcalorimeter observations. With the recent developments of the spectral simulation code Cloudy, inspired by the high spectral resolution of the X-Ray Imaging and Spectroscopy Mission (XRISM) and the Advanced Telescope for High Energy Astrophysics (Athena), we make predictions for the intensity ratio of the resolved fine-structure lines Ly$\alpha_1$ and Ly$\alpha_2$ of H-like ions. We show that this ratio can be observationally constrained and used as a plasma column density indicator. We demonstrate this with a XRISM observation of the high-mass X-ray binary Centaurus X-3. This diagnostic is useful for a wide range of X-ray emitting plasmas, either collisionally or radiatively ionized.

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Chamani M. Gunasekera, Peter A. M. van Hoof, Masahiro Tsujimoto, Gary J. Ferland. 2024-11-22. New Insights with XRISM & Cloudy: A novel Column Density Diagnostic. https://doi.org/10.1051/0004-6361%2F202453133

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