The Chandra observations of several gravitationally lensed quasars show evidence for flux and spectral variability of the X-ray emission that is uncorrelated between images and is thought to result from the microlensing by stars in the lensing galaxy .
We report here on the most detailed modeling of such systems to date , including simulations of the emission of the Fe K \alpha fluorescent radiation from the accretion disk with a general relativistic ray tracing code , the use of realistic microlensing magnification maps derived from inverse ray shooting calculations , and the simulation of the line detection biases .
We use lensing and black hole parameters appropriate for the quadruply lensed quasar RX J1131 - 1231 ( z _ { s } = 0.658 , z _ { l } = 0.295 ) , and compare the simulated results with the observational results .
The simulations can not fully reproduce the distribution of the detected line energies indicating that some of the assumptions underlying the simulations are not correct , or that the simulations are missing some important physics .
We conclude by discussing several possible explanations .