Multi-dimensional modelling of X-ray spectra for AGN accretion-disk outflows

TL;DR

This paper models X-ray spectra of AGN outflows using multi-dimensional Monte Carlo simulations, revealing how disk-wind geometries produce observable spectral features like blue-shifted absorption and Fe K emission lines.

Contribution

It introduces a multi-dimensional Monte Carlo approach to simulate AGN disk-wind spectra, highlighting the formation of spectral features consistent with observations.

Findings

Blue-shifted absorption features are produced in disk-wind geometries.

High-density winds can generate Fe K emission lines with extended red wings.

Models show potential to interpret real X-ray data from AGN like Mrk 766.

Abstract

We use a multi-dimensional Monte Carlo code to compute X-ray spectra for a variety of active galactic nucleus (AGN) disk-wind outflow geometries. We focus on the formation of blue-shifted absorption features in the Fe K band and show that line features similar to those which have been reported in observations are often produced for lines-of-sight through disk-wind geometries. We also discuss the formation of other spectral features in highly ionized outflows. In particular we show that, for sufficiently high wind densities, moderately strong Fe K emission lines can form and that electron scattering in the flow may cause these lines to develop extended red wings. We illustrate the potential relevance of such models to the interpretation of real X-ray data by comparison with observations of a well-known AGN, Mrk 766.