Two Populations of Diffuse Molecular Clouds
Abstract
The authors observed 16 diffuse clouds and eight high-latitude molecular clouds in the J = 2-1 transition of CO and 13CO and compared their properties. Results suggest that the diffuse clouds are not a homogeneous population of molecular clouds but can be divided into two groups depending on the column density of CO. One group consists of "CO-poor" clouds with N(CO) < 4×1014cm-2 and N(CO)/N(H) < 10-6. The other consists of "CO-rich" clouds with mean N(CO) = 4.2×1016cm-2 and N(CO)/N(H) ≈ 1.7×10-5. The high-latitude clouds resemble the CO-rich diffuse clouds.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1988
- DOI:
- 10.1086/185125
- Bibcode:
- 1988ApJ...326L..69L
- Keywords:
-
- Carbon Monoxide;
- Chemical Composition;
- Interstellar Chemistry;
- Molecular Clouds;
- Abundance;
- Hydrogen;
- Interstellar Extinction;
- Astrophysics;
- INTERSTELLAR: ABUNDANCES;
- INTERSTELLAR: MOLECULES