The CN radical in diffuse interstellar clouds.
Abstract
A survey of 15 lines of sight for the CN B2Sigma(+) X2Sigma(+) interstellar absorption lines shows that the CN column density in diffuse interstellar clouds follows the relation log N(CN) is proportional to m log N(H2), where m is approximately equal to 3. This result is reproduced by a reaction network in which CN is produced primarily from C2 by the neutral-neutral reaction C2 + N yields CN + C, and photodissociation is the main destruction pathway for the neutral molecules CH, C2, and CN. The CN radical is the first molecular species observed in diffuse clouds that requires a neutral-neutral reaction for its formation in the gas phase. The network also reproduces the observed ratio N(CN)/N(H2).
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1984
- DOI:
- 10.1086/162680
- Bibcode:
- 1984ApJ...287..219F
- Keywords:
-
- Absorption Spectra;
- Cyanogen;
- Diffuse Radiation;
- Interstellar Gas;
- Molecular Clouds;
- Photodissociation;
- Oscillator Strengths;
- Astrophysics