Mid-Infrared Imaging of Massive Star Forming Regions with Water Maser Emission
Abstract
We present a mid-infrared imaging survey of 26 sites of water maser emission. Observations were obtained at the InfraRed Telescope Facility 3-m telescope with the University of Florida mid-infrared imager/spectrometer OSCIR, and the JPL mid-infrared camera MIRLIN. The main purpose of the survey was to explore the relationship between water masers and the massive star formation process. We expand on the results of our earlier paper (De Buizer et al. 2003) that shows water masers are found to be associated in some cases with young embedded stars. These embedded sources may be high mass protostellar objects (HMPOs), or perhaps even young embedded intermediate mass stars given their mid-infrared luminosities. Some distributions of water masers with respect to the mid-infrared and/or radio sources on the field indicate that some water masers are associated with outflows from these objects. We also show that mid-infrared emission seems to be more closely associated with water and OH maser emission than cm radio continuum emission from UC HII regions. Furthermore, we find a high percentage of linearly distributed water masers in our sample (38%) as well as linearly distributed OH masers (50%). This shows that methanol masers are not the only maser population with linearly distributed maser groups. Given the mid-infrared morphologies of the sources associated with the masers and the outflow observations of De Buizer (2003), we conclude that the vast majority of linearly distributed masers are not tracing circumstellar disks, but outflows and shocks instead.
- Publication:
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American Astronomical Society Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AAS...20516601D