The Taurus Spitzer Survey: New Candidate Taurus Members Selected Using Sensitive Mid-Infrared Photometry
Stapelfeldt, K. R.; Wolf, S.; Audard, M.; Güdel, M.; Grosso, N.; Guieu, S.; Dougados, C.; Monin, J. -L.; Bouvier, J.; Evans, N. J.; Menard, F.; Noriega-Crespo, A.; Fukagawa, M.; Knapp, G. R.; Rebull, L. M.; Glauser, A. M.; Skinner, S. L.; Flagey, N.; Allen, L. E.; Padgett, D. L.; Hillenbrand, L. A.; Latter, W. B.; Briggs, K.; Baldovin-Saavedra, C.; Harvey, P.; Hines, D.; Strom, S.; McCabe, C. -E.; Carey, S. J.; Brooke, T.; Huard, T.; Terebey, S.; Angione, J. R.; Tromp, J.
United States, Switzerland, France, Japan, United Kingdom, Germany
Abstract
We report on the properties of pre-main-sequence objects in the Taurus molecular clouds as observed in seven mid- and far-infrared bands with the Spitzer Space Telescope. There are 215 previously identified members of the Taurus star-forming region in our ~44 deg2 map these members exhibit a range of Spitzer colors that we take to define young stars still surrounded by circumstellar dust (noting that ~20% of the bona fide Taurus members exhibit no detectable dust excesses). We looked for new objects in the survey field with similar Spitzer properties, aided by extensive optical, X-ray, and ultraviolet imaging, and found 148 new candidate members of Taurus. We have obtained follow-up spectroscopy for about half the candidate sample, thus far confirming 34 new members, three probable new members, and 10 possible new members, an increase of 15%-20% in Taurus members. Of the objects for which we have spectroscopy, seven are now confirmed extragalactic objects, and one is a background Be star. The remaining 93 candidate objects await additional analysis and/or data to be confirmed or rejected as Taurus members. Most of the new members are Class II M stars and are located along the same cloud filaments as the previously identified Taurus members. Among non-members with Spitzer colors similar to young, dusty stars are evolved Be stars, planetary nebulae, carbon stars, galaxies, and active galactic nuclei.