Identification of Galaxies in the Spitzer Taurus Survey: Comparison with the 2MASS Extended Source Catalog
Abstract
The Spitzer Taurus Survey, encompassing 43 square degrees, is sensitive to detecting new young stellar objects in Taurus. However the survey also contains numerous extragalactic objects, which are not easily distinguished from faint YSOs using standard color selection criteria. To characterize galaxies within the Taurus survey we did morphological classification in a subregion of all objects from the 2MASS extended source catalog (2MASX) that were identified as galaxies. We selected a roughly 1 square degree area that covers a range of extinctions and for which we had both infrared Spitzer and visual CFHT and SDSS images available. We examined the IRAC 3.6 micron infrared images of each 2MASX galaxy candidate, selecting those objects with a morphology demonstrating ellipticity with a well-defined major and minor axis and lacking diffraction spikes. For confirmation of our classification, we examined the visual images for evidence of common galactic attributes, such as spiral arms. We found roughly 74% of the objects classified as galaxies by the 2MASX catalog were indeed galaxies. Roughly 23% were multiple sources within 6 arcsec radius aperture in the higher spatial resolution data. A few galaxies were also multiple sources. There were about 5% miscellaneous sources including one known YSO and one stellar point source. We present the infrared and optical properties of the sample.
The Spitzer Space Telescope is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA.- Publication:
-
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 2007
- Bibcode:
- 2007AAS...211.1214O