Astrolunch by Moshe Elitzur (University of Kentucky)

Date: 
Tue, 25/05/201012:30-13:30
Location: 
Kaplun Bldg, seminar room, 2nd floor
The AGN Torus --- a Paradigm Change
The variety of observations of Active Galactic Nuclei (AGN) show that the nuclear activity is powered by a central massive black hole that drives radio emitting jets and ionizes surrounding line-emitting clouds. This central engine is surrounded by an obscuring torus, comprised of optically thick dusty clouds in a rotating configuration. The torus dynamical origin, and especially its vertical support, present a serious challenge.
We have recently developed the formalism for radiative transfer in clumpy media, and in this talk I show that past problems with modeling the AGN infrared emission find a natural explanation in clumpy torus models. Furthermore, the clumpy model may also provide the answer for the torus dynamical origin and solidify the case for a paradigm shift: the torus is apparently just the dusty region of wind outflow from the AGN accretion disk in which the clouds are optically thick.