Microlensing contribution to the lensed quasar X-ray spectra
Presenting author: Lukas Ledvina
In quasar microlensing the flux from a distant quasar is modulated by the gravitational lensing effect of individual stars in a galaxy lying in the foreground. The stars form a network of caustics that scan the surface of the quasar accretion disk passing in the background. We use a fully relativistic Kerr-metric thin-disk model to demonstrate the variation of the iron K alpha line originating from the inner disk with the changing position of the caustic on the emission map. We illustrate in detail different microlensing-generated features on the line profile. In particular, we discuss the effects involving the innermost stable circular orbit in the case of non-extremal Kerr black holes.