Models of the iron Kalpha fluorescence line and the Compton shoulder in irradiated accretion disk spectra
Abstract
We present a full set of model atmosphere equations for the accretion disk around a supermassive black hole irradiated by hard X-ray lamp of power-law spectral distribution. Model equations allow for multiple Compton scattering of radiation on free electrons, and for large relative photon-electron energy exchange at the time of scattering. We present spectra in specific intensities integrated over the disk surface. Theoretical outgoing intensity spectra show soft X-ray excess below 1 keV, and distinct Kalpha and Kbeta fluorescent lines of iron. We demonstrate the existence of the Compton Shoulder and claim that it can contribute to the asymmetry and equivalent widths of some observed Fe Kalpha lines in AGN. Our models exhibit the effect of limb-brightening in reflected X-rays.