Neutral carbon emission in M42.
Abstract
The detection and measurement of the forbidden C I lines at 9850 and 8727 A emitted by the Orion Nebula are reported. Typical values for the electron density needed to excite the lines collisionally in the H II-H I transition layers and for the neutral carbon column density are evaluated. The carbon ionization equilibrium is accounted for by invoking the predominance of charge exchange over radiative processes. Implications for the topology of the transition layers are suggested.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- August 1978
- Bibcode:
- 1978A&A....68L...7H
- Keywords:
-
- Atomic Spectra;
- Carbon;
- Hydrogen Clouds;
- Line Shape;
- Nebulae;
- Charge Exchange;
- Hydrogen Ions;
- Metastable Atoms;
- Photoionization;
- Power Spectra;
- Astrophysics;
- Carbon:H II Regions;
- H II Regions:Orion Nebula