Abstract
We consider the formation and evolution of vortices in a hydrodynamic shearing-sheet model. The evolution is done numerically using a version of the ZEUS code. Consistent with earlier results, an injected vorticity field evolves into a set of long-lived vortices, each of which has a radial extent comparable to the local scale height. But we also find that the resulting velocity field has a positive shear stress, 〈∑δvrδvφ〉. This effect appears only at high resolution. The transport, which decays with time as t-12, arises primarily because the vortices drive compressive motions. This result suggests a possible mechanism for angular momentum transport in low-ionization disks, with two important caveats: a mechanism must be found to inject vorticity into the disk, and the vortices must not decay rapidly due to three-dimensional instabilities.
Original language | English (US) |
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Pages (from-to) | 149-156 |
Number of pages | 8 |
Journal | Astrophysical Journal |
Volume | 635 |
Issue number | 1 I |
DOIs | |
State | Published - Dec 10 2005 |
Keywords
- Accretion, accretion disks
- Galaxies: active
- Galaxies: nuclei
- Solar system: formation
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science