Tracing Galactic Molecular Gas Using Infrared Excess Sources
Abstract
The optical depth of dust at 100 microns is used to trace the column density of dust in a 330 square degree region of the Galactic Plane. Using datasets from the Canadian Galactic Plane Survey, a majority of the dust is found to correlate with either the HI column density or the CO emission in the region. However, there exist regions where the dust content is greater than what is expected from the gaseous tracers. While some of these infrared excess sources are explained through an association with dust heated by energetic processes, a second population of infrared excess is devoid of warm dust. This class of infrared excess is related to other components of the cold interstellar medium, and may trace Galactic molecular hydrogen in regions where CO is an insufficient tracer of the distribution of molecular gas.
- Publication:
-
American Astronomical Society Meeting Abstracts #208
- Pub Date:
- June 2006
- Bibcode:
- 2006AAS...208.2101D