Title:  Microlensing the Quasar Accretion Disk

Speaker: Prof.  Xinyu Dai (University of Oklahoma)

Time: July 27, 2:00PM (tomorrow afternoon)

Location: 3rd floor, middle conference room

Abstract:

30 years after the discovery of the first cosmological lens,gravitational lensing has become an important tool in many different astrophysical applications. In particular, quasar microlensing provides a novel method to map the quasar accretion disk structure. Utilizing the dependence of microlensing variability on the source size, we are able to resolve the disk structure that is several orders of magnitude smaller than the angular resolution of our currenttelescopes. I will review the basic concepts of gravitational lensing, microlensing, and then present our measurements of quasar accretion disk sizes in about 10 systems using this method. In the end, I will discuss the future perspectives of gravitational lensing under the context of the next generation of large-scale surveys.