Mid-Infrared Selection of Brown Dwarfs and High-Redshift Quasars

Authors :: Michael J. I. Brown
Mark Brodwin
Howard A. Smith
Andrew Blain
Glenn P. Tiede
Anthony H. Gonzalez
J. D. Kirkpatrick
Arjun Dey
B. T. Soifer
Daniel Stern
Peter Eisenhardt
Lori Allen
Buell T. Jannuzi
K. Brand
Vandana Desai
C. Bian
Edward L. Wright
R. Cool
Karín Menéndez-Delmestre
Source :: Monash University
Publication Year :: 2007
Publisher :: American Astronomical Society, 2007.
Abstract: We discuss color selection of rare objects in a wide-field, multiband survey spanning from the optical to the mid-infrared. Simple color criteria simultaneously identify and distinguish two of the most sought after astrophysical sources: the coolest brown dwarfs and the most distant quasars. We present spectroscopically-confirmed examples of each class identified in the IRAC Shallow Survey of the Bootes field of the NOAO Deep Wide-Field Survey. ISS J142950.9+333012 is a T4.5 brown dwarf at a distance of approximately 42 pc, and ISS J142738.5+331242 is a radio-loud quasar at redshift z=6.12. Our selection criteria identify a total of four candidates over 8 square degrees of the Bootes field. The other two candidates are both confirmed 5.5<br />Comment: 19 pages, 7 figures; submitted to the Astrophysical Journal