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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
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.
  • Dust,
  • Extinction,
  • Galaxies,
  • Active,
  • High-redshift,
  • Starburst,
  • Infrared
Publication Date
April 1, 2005
Publisher Statement
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Citation Information
J. R. Houck, B. T. Soifer, D. Weedman, Sarah J.U. Higdon, et al.. "Spectroscopic Redshifts to z > 2 for Optically Obscured Sources Discovered with the Spitzer Space Telescope" The Astrophysical Journal Vol. 622 Iss. 2 (2005) p. 105 - 108
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