Title: Density Waves in Strongly Radiation Pressure Dominated AGN Accretion Disks 　　  

　　Speaker: Yan-Fei Jiang (姜燕飞, UC Santa Barbara ) 　　  

　　Time: 10 am, February 16 (Tuesday)  　　  

　　Location: Middle conference room, 3rd floor 　　  

　　Abstract:  　　  

　　AGN unification model is very successful to explain many observational properties of AGNs, however, little progress has been made to understand the physical properties of the inner accretion disks, where most of the photons are emitted. The radiation pressure in the inner region of AGN accretion disks can be 10^4 times larger than gas pressure for most quasars. I will show that in this strongly radiation pressure dominated regime, magneto-rotational instability is inefficient to provide the required angular momentum transfer for the accretion disks. Density waves excited by the turbulent flow can play an important role for the structures of AGN accretion disks. I will show numerical evidences and theoretical understanding of the density waves as well as their implications for AGN accretion disks.