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arXiv · 0903.1289

Mid-Infrared Spectroscopy of Optically Faint Extragalactic 70 micron Sources

D. Farrah·D. Weedman·C. Lonsdale·M. Polletta·M. Rowan-Robinson·J. Houck·H. Smith
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Abstract

We present mid-infrared spectra of sixteen optically faint sources with 70 micron fluxes in the range 19-38mJy. The sample spans a redshift range of 0.35 10mJy, the 70\um sample has steeper IR continua and higher luminosities. The PAH dominated sources are among the brightest starbursts seen at any redshift, and reside in a redshift range where other selection methods turn up relatively few sources. The absorbed sources are at higher redshifts and have higher luminosities than the PAH dominated sources, and may show weaker luminosity evolution. We conclude that a 70 micron selection extending to ~20mJy, in combination with selections at mid-IR and far-IR wavelengths, is necessary to obtain a complete picture of the evolution of IR-luminous galaxies over 0<z<2.

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D. Farrah, D. Weedman, C. Lonsdale, M. Polletta, M. Rowan-Robinson, J. Houck, H. Smith. 2009-03-06. Mid-Infrared Spectroscopy of Optically Faint Extragalactic 70 micron Sources. https://doi.org/10.1088/0004-637x%2F696%2F2%2F2044

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