Far-infrared observations of M17: the interaction of an H II region with a molecular cloud.
Abstract
The central 15' of the M17 H II region-molecular cloud complex has been mapped with 1' resolution simultaneously at 30, 50, and 100 tLm. The data suggest that the bulk of the luminosity radiated in the far-infrared is supplied by the exciting stars of the H II region; the far-infrared radiation is thermal emission from dust grains located chiefly outside the ionized gas. Large-scale systematic gradients in both the temperature and the column density of the dust are seen across the source. The appearance of the source in the far-infrared reflects the markedly nonuniform distribution of matter around the exciting stars; the H II region is bounded by the molecular cloud to the southwest. The core of the molecular cloud is heated primarily by infrared radiation from dust within and adjacent to the H II region; no evidence is seen for substantial luminosity sources embedded within the molecular cloud. Subject headings: infrared: sources - interstellar: matter - interstellar: molecules - nebulae: individual
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1979
- DOI:
- 10.1086/157418
- Bibcode:
- 1979ApJ...233..575G
- Keywords:
-
- Far Infrared Radiation;
- H Ii Regions;
- Infrared Astronomy;
- Interstellar Matter;
- Interstellar Radiation;
- Cosmic Dust;
- Hydrogen Ions;
- Ionized Gases;
- Plasma Clouds;
- Stellar Evolution;
- Stellar Luminosity;
- Thermal Emission;
- Astrophysics;
- H II Regions:Infrared Radiation;
- H II Regions:Molecular Clouds