The Kelvin-Helmholtz Interface Instability in the Interstellar Environment. II. Interstellar Cloud Rotation
Abstract
It is suggested that interstellar clouds may derive their rotation from the vortex flow associated with the nonlinear Kelvin-Helmholtz 'rollup' accompanying shear flows in the interstellar medium. The predicted maximum angular velocity, expressed as a ratio with respect to the galactic background, is 100 R(pc) exp -1/2 for a cloud radius R(pc), and the corresponding specific angular momentum is 3 x 10 to the 23rd R(pc) exp 3/2 sq cm/sec. These predictions nicely match the upper envelope of values reported for rotating clouds. It is concluded that, for those clouds that are rotating, the Kelvin-Helmholtz instability is a viable candidate for providing angular momentum to interstellar material.
- Publication:
-
The Astronomical Journal
- Pub Date:
- March 1989
- DOI:
- 10.1086/115023
- Bibcode:
- 1989AJ.....97..783F
- Keywords:
-
- Interstellar Gas;
- Kelvin-Helmholtz Instability;
- Molecular Clouds;
- Angular Momentum;
- Gravitational Effects;
- Shear Flow;
- Velocity Distribution;
- Astrophysics;
- INTERSTELLAR: MATTER