Density wave theory for spiral galaxies - Effects of resonant stars at corotation
Abstract
Density wave theory has already shown that galaxy disks can support discrete self-excited spiral modes independently of resonant effects at corotation. However, in the problem of excitation of spiral modes in more general galaxy models, and especially in the mechanism for selection of the prominent structures, energy and angular momentum exchange with the corotating stars might play an important role. In order to study these resonant effects and give a quantitative discussion of their importance, we improve the simple asymptotic differential equation that was previously used to calculate spiral modes. We find that the stellar dynamic evaluation of the resonant contribution is quite different from what was argued previously on the basis of a fluid model. Generally, in realistic galaxy models resonant effects at corotation are less important than expected.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1982
- Bibcode:
- 1982A&A...108..265B
- Keywords:
-
- Density Wave Model;
- Galactic Structure;
- Spiral Galaxies;
- Stellar Rotation;
- Angular Momentum;
- Astronomical Models;
- Asymptotic Methods;
- Differential Equations;
- Energy Transfer;
- Fluid Dynamics;
- Momentum Transfer;
- Resonance;
- Astrophysics