Stability of Toomre-Hayashi Disk
| dc.creator | Hanawa, Tomoyuki | |
| dc.creator | Saigo, Kazuya | |
| dc.creator | Matsumoto, Tomoaki | |
| dc.date | 2000-10-04 | |
| dc.date.accessioned | 2026-07-07T01:55:48Z | |
| dc.date.available | 2026-07-07T01:55:48Z | |
| dc.description | We investigate stability of Toomre-Hayashi model for a self-gravitating, rotating gas disk. The rotation velocity, $ v_ϕ$, and sound speed, $ c _{\rm s} $, are spatially constant in the model. We show that the model is unstable against an axisymmetric perturbation irrespectively of the values of $ v_ϕ$ and $ c_{\rm s} $. When the ratio, $ v_ϕ/ c_{\rm s} $, is large, the model disk is geometrically thin and unstable against an axisymmetric perturbation having a short radial wavelength, i.e., unstable against fragmentation. When $ v_ϕ/ c_{\rm s} $ is smaller than 1.20, it is unstable against total collapse. Toomre-Hayashi model of $ 1.7 \la v_ϕ/ c_{\rm s} \la 3 $ was thought to be stable against axisymmetric perturbations in earlier studies in which only radial motion was taken into account. Thus, the instability of Toomre-Hayashi model having a medium $ v_ϕ/ c_{\rm s} $ is due to not change in the surface density but that in the disk height. We also find that the singular isothermal perturbation is stable against non-spherical peturbations. | |
| dc.description | AAS LaTeX, 11 pages including 4 figures, submitted to Astrophysical Journal in September | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0010081 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0010081 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/1781 | |
| dc.subject | Astrophysics | |
| dc.title | Stability of Toomre-Hayashi Disk | |
| dc.type | text |