THE NORTH AMERICAN AND PELICAN NEBULAE. I. IRAC OBSERVATIONS
- Spitzer Science Center/Caltech, M/S 220-6, 1200 E. California Blvd., Pasadena, CA 91125 (United States)
- Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)
- Jet Propulsion Laboratory, MS 183-900, California Institute of Technology, Pasadena, CA 91109 (United States)
We present a 9 deg{sup 2} map of the North American and Pelican Nebulae regions obtained in all four Infrared Array Camera (IRAC) channels with the Spitzer Space Telescope. The resulting photometry is merged with that at JHK{sub s} from Two Micron All Sky Survey and a more spatially limited BVI survey from previous ground-based work. We use a mixture of color-color diagrams to select a minimally contaminated set of more than 1600 objects that we claim are young stellar objects (YSOs) associated with the star-forming region. Because our selection technique uses infrared excess as a requirement, our sample is strongly biased against inclusion of Class III YSOs. The distribution of IRAC spectral slopes for our YSOs indicates that most of these objects are Class II, with a peak toward steeper spectral slopes but a substantial contribution from a tail of Flat spectrum and Class I type objects. By studying the small fraction of the sample that is optically visible, we infer a typical age of a few Myr for the low-mass population. The young stars are clustered, with about a third of them located in eight clusters that are located within or near the LDN 935 dark cloud. Half of the YSOs are located in regions with surface densities higher than 1000 YSOs/deg{sup 2}. The Class I objects are more clustered than the Class II stars.
- OSTI ID:
- 21300530
- Journal Information:
- Astrophysical Journal, Vol. 697, Issue 1; Other Information: DOI: 10.1088/0004-637X/697/1/787; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
The Spitzer survey of interstellar clouds in the gould belt. VI. The Auriga-California molecular cloud observed with IRAC and MIPS
THE NORTH AMERICAN AND PELICAN NEBULAE. II. MIPS OBSERVATIONS AND ANALYSIS