A Dark-Cloud Complex in Aquila: Small Molecular Clouds Possibly Associated with the Aquila Rift
Abstract
A 12CO(J = 1-0) survey for local molecular clouds was performed toward dark clouds in Aquila (26° < l ≤ 42° and -25° ≤ b < -2°) by using the 4-meter millimeter wave telescope, NANTEN, at Las Campanas Observatory, Chile. A cloud complex consisting of 64 small clouds has been discovered in -25° ≲ b ≲ -12°; at a distance of 220 pc, its height from the galactic plane is ∼ 50-100 pc and the total mass is ∼ 4 × 103M⊙. The spatial and velocity distributions of the complex suggest that it may be connected to the Great Rift in Aquila. This complex, as a whole, has a significantly large virial mass compared with the mass derived from the CO intensities by an order of magnitude, though H I gas of ∼ 104M⊙, possibly associated, may contribute to bind them gravitationally. The individual CO clouds have velocity dispersion and mass similar to those of the high-latitude clouds; also, the clouds are not in gravitational equilibrium. There is no indication of active star formation.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- December 1999
- DOI:
- 10.1093/pasj/51.6.851
- Bibcode:
- 1999PASJ...51..851K
- Keywords:
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- GALAXY: STRUCTURE;
- ISM: CLOUDS;
- ISM: INDIVIDUAL (AQUILA DARK CLOUDS);
- ISM: MOLECULES;
- STARS: FORMATION;
- Galaxy: structure;
- ISM: clouds;
- ISM: individual (Aquila dark clouds);
- ISM: molecules;
- stars: formation