Quantification of stochastic fragmentation of self-gravitating discs
Abstract
Using 2D smoothed particle hydrodynamics, we investigate the distribution of wait times between strong shocks in a turbulent, self-gravitating accretion disc. We show that the resulting distributions do not depend strongly on the cooling time or resolution of the disc and that they are consistent with the predictions of earlier work. We use the distribution of wait times between shocks to estimate the likelihood of stochastic fragmentation by gradual contraction of shear-resistant clumps on the cooling time-scale. We conclude that the stochastic fragmentation mechanism cannot change the radius at which fragmentation is possible by more than ∼20 per cent, restricting direct gravitational collapse as a mechanism for giant planet formation to the outer regions of protoplanetary discs.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- January 2016
- DOI:
- 10.1093/mnras/stv2378
- arXiv:
- arXiv:1510.05290
- Bibcode:
- 2016MNRAS.455.1438Y
- Keywords:
-
- planets and satellites: formation;
- protoplanetary discs;
- Astrophysics - Earth and Planetary Astrophysics;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted for publication in MNRAS. 6 pages and 3 figures