Vortices in self-gravitating gaseous discs

Details Vortices in self-gravitating gaseous discs Vortices in self-gravitating gaseous discs

2009-01-12

arxiv.org/abs/0901.1617v1

Astronomy and Astrophysics

Astrophysics

Earth and Planetary Astrophysics

12 pages, 6 figures, accepted for publication in MNRAS

Scientific paper

10.1111/j.1365-2966.2009.14481.x

(abridged) Vortices are believed to play a role in the formation of km-sized planetesimals. However, vortex dynamics is commonly studied in non-self-gravitating discs. The main goal here is to examine the effects of disc self-gravity on vortex dynamics. For this purpose, we employ the 2D self-gravitating shearing sheet approximation. A simple cooling law with a constant cooling time is adopted, such that the disc settles down into a quasi-steady gravitoturbulent state. In this state, vortices appear as transient structures undergoing recurring phases of formation, growth to sizes comparable to a local Jeans scale and eventual shearing and destruction due to the combined effects of self-gravity and background Keplerian shear. Each phase typically lasts about 2 orbital periods or less. As a result, in self-gravitating discs the overall dynamical picture of vortex evolution is irregular consisting of many transient vortices at different evolutionary stages and, therefore, with various sizes up to the local Jeans scale. Vortices generate density waves during evolution, which turn into shocks. Therefore, the dynamics of density waves and vortices are coupled implying that, in general, one should consider both vortex and spiral density wave modes in order to get a proper understanding of self-gravitating disc dynamics. Our results suggest that given such an irregular and rapidly varying character of vortex evolution in self-gravitating discs, it may be difficult for such vortices to effectively trap dust particles. Further study of the behaviour of dust particles embedded in a self-gravitating gaseous disc is, however, required to strengthen this conclusion.

Affiliated with

Also associated with

No associations

Rating

Vortices in self-gravitating gaseous discs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Vortices in self-gravitating gaseous discs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vortices in self-gravitating gaseous discs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-533028