Stellar bars in disk galaxies: from banyans to butterflies?

摘要

We provide a non-linear orbit analysis of an evolving self-consistent model galaxy consisting of a two-component disk (stars + gas) and a live halo. We find that dynamical instabilities become milder in the presence of the gas component, and that the stability of planar and 3D stellar orbits is strongly affected by the related changes in the gravitational potential - both are destabilized with the gas accumulation at the center. This results in the overall weakening of the stellar bar and its dissolution on the time scale of a few 10(9) years. (C) 1999 Elsevier Science B.V. All rights reserved. [References: 18]