X-ray reflection in Galactic black hole candidates: Smeared edge profiles and resonant Auger destruction

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 Kα 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 Kα lines very difficult to detect in highly ionized inclined discs. We detail the physics of resonant Auger destruction at the level at which it is currently understood and point out its implications.