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arXiv · 0911.3176

The Taurus Spitzer Survey: New Candidate Taurus Members Selected Using Sensitive Mid-Infrared Photometry

L. M. Rebull·D. L. Padgett·C. -E. McCabe·L. A. Hillenbrand·K. R. Stapelfeldt·A. Noriega-Crespo·S. J. Carey·T. Brooke·T. Huard·S. Terebey·M. Audard·J. -L. Monin·M. Fukagawa·M. Guedel·G. R. Knapp·F. Menard·L. E. Allen·J. R. Angione·C. Baldovin-Saavedra·J. Bouvier·K. Briggs·C. Dougados·N. J. Evans·N. Flagey·S. Guieu·N. Grosso·A. M. Glauser·P. Harvey·D. Hines·W. B. Latter·S. L. Skinner·S. Strom·J. Tromp·S. Wolf
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Abstract

We report on the properties of pre-main-sequence objects in the Taurus molecular clouds as observed in 7 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 square degree 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 bonafide 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 candidate new members of Taurus. We have obtained follow-up spectroscopy for about half the candidate sample, thus far confirming 34 new members, 3 probable new members, and 10 possible new members, an increase of 15-20% in Taurus members. Of the objects for which we have spectroscopy, 7 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 AGN.

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L. M. Rebull, D. L. Padgett, C. -E. McCabe, L. A. Hillenbrand, K. R. Stapelfeldt, A. Noriega-Crespo, S. J. Carey, T. Brooke, T. Huard, S. Terebey, M. Audard, J. -L. Monin, M. Fukagawa, M. Guedel, G. R. Knapp, F. Menard, L. E. Allen, J. R. Angione, C. Baldovin-Saavedra, J. Bouvier, K. Briggs, C. Dougados, N. J. Evans, N. Flagey, S. Guieu, N. Grosso, A. M. Glauser, P. Harvey, D. Hines, W. B. Latter, S. L. Skinner, S. Strom, J. Tromp, S. Wolf. 2009-11-16. The Taurus Spitzer Survey: New Candidate Taurus Members Selected Using Sensitive Mid-Infrared Photometry. https://doi.org/10.1088/0067-0049%2F186%2F2%2F259

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