A Physical Mechanism for Bursts of Star Formation
Abstract
Star formation in galaxies is often associated with large-scale disturbances such as density waves and direct and tidal galaxy encounters. An explanation based on the nonlinear behavior of the Oort model for interstellar cloud evolution and star formation when subjected to such perturbations is suggested. The behavior depends critically on only one parameter: the ratio of the time delay between the formation of massive star-forming clouds and the disruption of these clouds by internal stellar winds and explosions to the equilibrium collision time scale. When this ratio is much smaller than unity, the system is extremely stable. However, as this ratio increases toward unity and larger, the system exhibits limit cycles and eventually a transition to chaotic behavior, in both cases accompanied by bursts of star formation. The possible relevance of these results to a variety of galactic phenomena, especially star formation bursts induced by tidal encounters between galaxies, is discussed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 1986
- DOI:
- 10.1086/163874
- Bibcode:
- 1986ApJ...301...77S
- Keywords:
-
- Galactic Evolution;
- Molecular Clouds;
- Star Distribution;
- Star Formation;
- Astronomical Models;
- Density Wave Model;
- Interstellar Gas;
- Oort Cloud;
- Perturbation Theory;
- Stellar Winds;
- Tides;
- Astrophysics;
- GALAXIES: STELLAR CONTENT;
- STARS: FORMATION