On the warm absorber in AGN outflow

TL;DR

This paper models the warm absorber in the Seyfert 1 galaxy Mrk 509 using a pressure equilibrium approach, successfully reproducing observed absorption features with a single slab of ionised gas.

Contribution

It introduces a novel modeling approach of the warm absorber as a single pressure-equilibrium slab, contrasting with traditional constant density models.

Findings

Successful modeling of the absorption measure distribution (AMD) with a single slab.

Demonstration that pressure equilibrium models can explain observed absorption features.

Discussion of the transmitted spectrum after passing through the warm absorber.

Abstract

Warm absorber (WA) is an ionised gas present in the line of sight to the AGN central engine. The effect of the absorber is imprinted in the absorption lines observed in X-ray spectra of AGN. In this work, we model the WA in Seyfert 1 galaxy Mrk 509 using its recently published shape of broad band spectral energy distribution (SED) as a continuum illuminating the absorber. Using the photoionization code {\sc Titan}, recently we have shown that the absorption measure distribution (AMD) found for this object can be successfully modelled as a single slab of gas in total pressure (radiation+gas) equilibrium, contrary to the usual models of constant density multiple slabs. We discuss the transmitted spectrum that would be recorded by an observer after the radiation from the nucleus passes through the WA.