X-ray reflection in Galactic Black Hole Candidates: smeared edge profiles and resonant Auger destruction

TL;DR

This paper models X-ray reflection spectra from accretion disks around Galactic black holes, showing that smeared iron K edges match observations and that resonant Auger destruction can obscure iron Kα lines in certain conditions.

Contribution

It introduces detailed modeling of iron K edge profiles and highlights the role of resonant Auger destruction in shaping observable X-ray features.

Findings

Smeared iron K edge profiles fit observational data well.

Resonant Auger destruction can suppress iron Kα lines in highly ionized disks.

Doppler broadening contributes to line profile shaping.

Abstract

We consider the spectra of Thomson-thick, geometrically-thin accretion discs around Galactic black hole candidates in the reflection model and compute their iron K edges and iron K$\alpha$ lines. We compare the smeared iron K edge profiles that we compute with observation and find them to be a satisfactory description of the data. We find that a combination of Doppler broadening and resonant Auger destruction of line photons can make iron K$\alpha$ lines very difficult to detect in highly ionized inclined discs. We detail the physics of resonant Auger destruction at the level it is currently understood and point out its implications.