Amplification and variability of the AGN X-ray emission due to   microlensing
  We consider the contribution of microlensing to the AGN Fe K$\alpha$ line and X-ray continuum amplification and variation. To investigate the variability of the line and X-ray continuum, we studied the effects of microlensing on quasar X-ray spectra produced by crossing of a microlensing pattern across a standard relativistic accretion disk. To describe the disk emission we used a ray tracing method considering both metrics, Schwarzschild and Kerr. We found that the Fe K$\alpha$ and continuum may experience significant amplification by a microlensing event (even for microlenses of very small mass). Also, we investigate a contribution of microlensing to the X-ray variability of high-redshifted QSOs, finding that cosmologically distributed deflector may contribute significantly to the X-ray variability of high-redshifted QSOs (z>2). 
L. C. Popovic, P. Jovanovic, T. Petrovic, V. N. Shalyapin