Abstract
In this paper we examine the issue of characterizing the transport
associated with gravitational instabilities in relatively cold discs,
discussing in particular under which condition it can be described
within a local, viscous framework. We present the results of global,
three-dimensional, SPH simulations of self-gravitating accretion discs,
in which the disc is cooled using a simple parameterization for the
cooling function. Our simulations show that the disc settles in a
``self-regulated'' state, where the axisymmetric stability parameter Q ~
1 and where transport and energy dissipation are dominated by
self-gravity. We have computed the gravitational stress tensor and
compared our results with expectations based on a local theory of
transport. We find that, for disc masses smaller than 0.25M* and aspect
ratio H/r
| Original language | English |
|---|---|
| Title of host publication | PLASMAS IN THE LABORATORY AND IN THE UNIVERSE |
| Subtitle of host publication | New Insights and New Challenges |
| Publisher | AIP PRESS |
| Pages | 266-271 |
| Volume | 703 |
| Publication status | Published - 1 Apr 2004 |
Keywords / Materials (for Non-textual outputs)
- Accretion and accretion disks
- Magnetohydrodynamics and plasmas