The energetics of molecular clouds. III. The S235 molecular cloud.
Abstract
The molecular cloud associated with the S235 H II region has been studied by means of molecular lines and near-infrared observations. The cloud consists of two components, one of which partly surrounds the S235 H II region. The other component contains a dense, hot region of active star formation, marked by self-reversed CO profiles, compact H II regions, masers, and infrared sources. From the molecular line data, the size and mass of the two components are estimated to be 6-8 pc and 3000-4000 solar masses. More detailed studies near the region of active star formation yield estimates of density (approximately 200,000-500,000/cu cm) and the abundances of H2CO, HCO(+), HCN, and (C-13)O. Analysis of the energetics suggests that the cloud is heated by the exciting star of S235 and by the exciting stars of the compact H II regions. Assuming that the gas is heated by collisions with warm dust grains, the far-infrared luminosity has been predicted. The observations of far-infrared emission are in reasonable agreement with predictions.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1981
- DOI:
- 10.1086/158937
- Bibcode:
- 1981ApJ...246..394E
- Keywords:
-
- Gas Temperature;
- Interstellar Gas;
- Molecular Clouds;
- Near Infrared Radiation;
- Stellar Evolution;
- Abundance;
- Cosmic Dust;
- Emission Spectra;
- Gas Density;
- H Ii Regions;
- Infrared Astronomy;
- Interstellar Masers;
- Mass;
- Size Determination;
- Astrophysics