The impact of accretion disk winds on the X-ray spectrum of AGN: Part 2 - XSCORT + Hydrodynamic Simulations

TL;DR

This study combines XSCORT with hydrodynamic simulations to analyze how accretion disk winds influence the X-ray spectra of AGN, revealing angle-dependent spectral features and challenging existing models of soft X-ray excess.

Contribution

It introduces a novel approach integrating XSCORT with hydrodynamic simulations to study AGN wind effects on X-ray spectra, highlighting the impact of viewing angle and accretion rate.

Findings

Equatorial lines-of-sight show Compton scattering and neutral absorption.

Polar lines-of-sight produce featureless spectra.

Transition regions exhibit diverse absorption features and highly-ionized, blue-shifted Fe lines.

Abstract

abridged: We use XSCORT, together with the hydrodynamic accretion disc wind simulation from Proga & Kallman (2004), to calculate the impact that the accretion disk wind has on the X-ray spectrum from a 1E8 solar mass black hole Active Galactic Nuclei (AGN) accreting at 0.5 L/L_Edd. The properties of the resulting spectra depend on viewing angle and clearly reflect the distinct regions apparent in the original hydrodynamic simulation. Very equatorial lines-of-sight (l.o.s) are dominated by Compton scattering and nearly-neutral absorption. Polar l.o.s result in largely featureless spectra. Finally, l.o.s that intersect the transition region between these extremes have a wide range of absorption features imprinted on the spectrum. Both polar and transition region l.o.s produce spectra that show highly-ionized, blue-shifted, Fe absorption features that are qualitatively similar to features observed in the X-ray spectra of a growing number of AGN. The spectra presented here clearly demonstrate that current simulations of line driven AGN accretion disk winds cannot reproduce the smooth soft X-ray excess. Furthermore, they predict that high accretion rate (L/L_Edd) AGN are likely to be strongly affected by obscuration, in sharp contrast to the clean picture that is generally assumed, based on the observed relation between the opening angle of the molecular torus and AGN luminosity.