X-ray plasma diagnostics for totally and partially photoionized plasmas such as Warm Absorber in AGN

TL;DR

This paper introduces advanced X-ray plasma diagnostics using high-resolution spectra to analyze photoionized plasmas in astrophysical objects like AGN, enabling better understanding of their central regions.

Contribution

It presents novel diagnostic methods based on line ratios of He-like ions for totally and partially photoionized plasmas, applicable to various hot astrophysical environments.

Findings

Resolved line splitting in low Z He-like ions with new X-ray satellites

Diagnostic techniques for plasma density, ionization, and temperature

Application to Warm Absorbers in Active Galactic Nuclei

Abstract

Thanks to the new generation of X-ray satellites such as Chandra and XMM, high resolution and high sensitivity spectra are available. In particular, for the first time, the three most intense lines (resonance, intercombination and forbidden) of low charged (low Z) He-like ions are splitted for non solar plasmas. We present density, ionizing process and temperature diagnostics, for totally and partially photoionized plasmas, based on ratios of these three lines. These powerful plasma diagnostics could be used for hot astrophysical plasmas such as AGN, starburst galaxies, X-ray binaries, etc. In particular, they could be applied to Warm Absorber often seen in Active Galactic Nuclei (Porquet & Dubau 2000), which is an important key tool to understand central region of different types of AGN (Seyfert 1 and 2, high and low redshift quasars).