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Article
Spectroscopic Redshifts to z > 2 for Optically Obscured Sources Discovered with the Spitzer Space Telescope
The Astrophysical Journal (2005)
  • J. R. Houck, Cornell University
  • B. T. Soifer, California Institute of Technology
  • D. Weedman, Cornell University
  • Sarah J.U. Higdon, Cornell University
  • J. L. Higdon, Cornell University
  • T. L. Herter, Cornell University
  • M. J. I. Brown, Princeton University
  • A. Dey, National Optical Astronomy Observatory
  • B. T. Jannuzi, National Optical Astronomy Observatory
  • E. Le Floc'h, University of Arizona
  • M. J. Rieke, University of Arizona
  • L. Armus, California Institute of Technology
  • V. Charmandaris, Cornell University
  • B. R. Brandl, Leiden Observatory
  • H. I. Teplitz, California Institute of Technology
Abstract
We have surveyed a field covering 9.0 deg2 within the NOAO Deep Wide-Field Survey region in Bootes with the Multiband Imaging Photometer on the Spitzer Space Telescope (SST) to a limiting 24 μm flux density of 0.3 mJy. Thirty-one sources from this survey with F24 μm > 0.75 mJy that are optically very faint (R  24.5 mag) have been observed with the low-resolution modules of the Infrared Spectrograph on SST (IRS). Redshifts derived primarily from strong silicate absorption features are reported here for 17 of these sources; 10 of these are optically invisible (R  26 mag), with no counterpart in BWR, or I. The observed redshifts for 16 sources are 1.7 < z < 2.8. These represent a newly discovered population of highly obscured sources at high redshift with extreme infrared-to-optical ratios. Using IRS spectra of local galaxies as templates, we find that a majority of the sources have mid-infrared spectral shapes most similar to ultraluminous infrared galaxies powered primarily by active galactic nuclei. Assuming that the same templates also apply at longer wavelengths, bolometric luminosities exceed 1013 L.
Keywords
  • Dust,
  • Extinction,
  • Galaxies,
  • Active,
  • High-redshift,
  • Starburst,
  • Infrared
Publication Date
April 1, 2005
DOI
10.1086/429405
Publisher Statement
This version of the paper was obtained from arXIV.org. In order for the work to be deposited in arXIV.org, the author must have copyright or it must be available under the Creative Commons Attribution license,Creative Commons Attribution-Noncommercial-ShareAlike license, orCreate Commons Public Domain Declaration. The publisher's final edited version of this article will be available at The Astrophysical Journal.
Citation Information
J. R. Houck, B. T. Soifer, D. Weedman, Sarah J.U. Higdon, et al.. "Spectroscopic Redshifts to z &gt; 2 for Optically Obscured Sources Discovered with the Spitzer Space Telescope" The Astrophysical Journal Vol. 622 Iss. 2 (2005) p. 105 - 108
Available at: http://works.bepress.com/sarah_higdon/21/