Christian Sorgenfrei   (Germany)

c.sorgenfrei @ stud.uni-heidelberg.de

Determining the innermost structure of quasars by microlensing: Measuring, simulating and interpreting lightcurves of multiple quasars

This project makes use of the gravitational microlensing effect to study the innermost structure of quasars.

We use light curves of multiply lensed quasars obtained at the Las Cumbres Observatory (LCO). After correcting for time delays between the images, uncorrelated brightness variations in the different quasar images can be detected. These are due to the microlensing of compact objects (such as stars) in the lensing galaxy.

Using this effect, we test model predictions for the brightness and temperature profiles of the accretion disk in the central quasar engine. The observations are compared to results from other methods, such as black hole mass determinations due to spectroscopy.

Supervisor:    Joachim Wambsganss    (ARI)