37^th Seminar

Fragmentation in self-gravitating accretion disks; Influence of binary systems

Jannes Klee

University of Kiehl

Abstract

Self-gravitation can play a role in protoplanetary- and AGN-disks. If they are massive enough, gravitoturbulence sets in and acts as a strong driver for angular momentum redistribution. Thereby it moves large amounts of gas from the outer parts of the disk to the central object. However, if the disk cools too fast its gas will fragment into bound objects, i.e. stars or planets, which alter the accretion in the following. The detailed circumstances, which lead to fragmentation are not fully understood. Different codes show different behavior in terms of fragmentation for ever higher resolutions and the same physical setup. We show that especially the shock handling can have a strong influence on the outcome of these kind of simulations. At the same time the physical quantities like external irradiation and torques, or the composition of the gas have an influence on the gravitoturbulent state. Here, we want to focus on massive circumbinary disks and discuss how they might alter fragmentation in self-gravitating disks.