Self-gravitating accretion disks in active galactic nuclei

The paper considers self-gravitating accretion disks in active galactic nuclei (AGN), assuming that most of the incoming fuel forms a thin accretion disk at distances for approx. 10 - 103pc from a supermassive black hole. The thermal and dynamical properties of the accretion disk are analysed, and it is concluded that its energetics is likely to be dominated by backscattered AGN radiation. The conditions under which Jeans fragmentation of such a disk into weakly interacting cloudlets can be avoided are also discussed, and a necessary condition for disk fragmentation to occur is given. (author)