CANCELLED Due to Travel Issues from East Coast Blizzard! ASTRONOMY COLLOQUIUM: Global Radiation MHD Simulations of Black Hole Accretion Disks
Please note that this talk is also part of the MICDE seminar series (http://micde.umich.edu/seminar-series/).
New results from a study of the magnetohydrodynamics of luminous accretion flows around black holes will be presented. In this regime, radiation pressure dominates the flow. Thus the calculations require numerical methods based on a formal solution of the time-dependent radiation transfer equation; we describe new algorithms we have developed that eliminate the need for approximate closures. We find that turbulent transport of radiation energy can be a significant contribution to the cooling rate in the disk, and this changes the global properties of the flow compared to standard thin-disk models. We describe new work to extend our calculations to full general relativity, in order to follow the dynamics in the innermost regions of the disk.