Structure and physics of cool giant molecular complexes.
Abstract
The interstellar medium is observed to be fragmented at all scales ranging from that of the supercloud complexes to that of the protostellar cores, forming a hierarchy which is not self-similar. In the solar neighborhood, the self-similarity breaks down at a salient scale which can be called that of 'clouds': their mass is several 100 solar masses, their size a few parsecs. The clouds, building blocks of the hierarchy, are supported against gravity by supersonic but subAlfvenic turbulence. It is shown that this turbulence can be fed, via MHD waves, over several 10s of Myr, by a pumping of the orbital kinetic energy of the other clouds within the same complex. It is also shown that local gravitational instabilities may develop within the gravitationally stable clouds and eventually form dense protostellar cores.
- Publication:
-
Physical Processes in Interstellar Clouds
- Pub Date:
- 1987
- DOI:
- 10.1007/978-94-009-3945-5_4
- Bibcode:
- 1987ASIC..210...59F
- Keywords:
-
- Astronomical Maps;
- Galactic Structure;
- Interstellar Chemistry;
- Molecular Clouds;
- H Ii Regions;
- Magnetohydrodynamic Waves;
- Millimeter Waves;
- Star Formation;
- Velocity Distribution;
- Astrophysics;
- Magnetohydrodynamics:Molecular Clouds;
- Molecular Clouds:Evolution;
- Molecular Clouds:Kinematics;
- Molecular Clouds:Magnetohydrodynamics;
- Molecular Clouds:Structure;
- Molecular Clouds:Turbulence