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

TL;DR

This paper enhances a Monte Carlo radiative transfer code to generate realistic X-ray spectra of AGN outflows, enabling better interpretation of observational data and confirming the presence of massive winds in specific quasars.

Contribution

The authors extend their spectral modeling code to include more atomic physics and plasma conditions, improving the realism and applicability of theoretical spectra for AGN outflows.

Findings

The improved models can reproduce observed X-ray features of AGN outflows.

Application to PG1211+143 confirms the presence of a massive outflow.

Enhanced code allows for broader plasma conditions in spectral simulations.

Abstract

Highly-ionized fast accretion-disk winds have been suggested as an explanation for a variety of observed absorption and emission features in the X-ray spectra of Active Galactic Nuclei. Simple estimates have suggested that these flows may be massive enough to carry away a significant fraction of the accretion energy and could be involved in creating the link between supermassive black holes and their host galaxies. However, testing these hypotheses, and quantifying the outflow signatures, requires high-quality theoretical spectra for comparison with observations. Here we describe extensions of our Monte Carlo radiative transfer code that allow us to generate realistic theoretical spectra for a much wider variety of disk wind models than possible in our previous work. In particular, we have expanded the range of atomic physics simulated by the code so that L- and M-shell ions can now be included. We have also substantially improved our treatment of both ionization and radiative heating such that we are now able to compute spectra for outflows containing far more diverse plasma conditions. We present example calculations that illustrate the variety of spectral features predicted by parametrized outflow models and demonstrate their applicability to the interpretation of data by comparison with observations of the bright quasar PG1211+143. We find that the major features in the observed 2 - 10 keV spectrum of this object can be well-reproduced by our spectra, confirming that it likely hosts a massive outflow.