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Mid-infrared selection of dusty AGN

Lacy, M. and Sajina, A. and Canalizo, G. (2006) Mid-infrared selection of dusty AGN. In: The Spitzer Space Telescope: New Views of the Cosmos. ASP Conference Series. No.357. Astronomical Society of the Pacific , San Francisco, CA, pp. 255-258. ISBN 978-1-583812-25-9.

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We present results from the spectroscopic follow-up of a sample of candidate obscured AGN selected in the mid-infrared from the Spitzer First Look Survey. Our selection allows a direct comparison of the numbers of obscured and unobscured AGN at a given luminosity for the first time, and shows that the ratio of obscured to unobscured AGN in an 8μm-selected sample with infrared luminosities corresponding to low luminosity quasars is ≈ 1 : 1 at z ~0.5. Most of our optically-faint candidate obscured AGN have the high-ionization, narrowline spectra expected from type-2 AGN. We discuss techniques for selecting such samples at longer infrared wavelengths to reduce the selection bias against highly-obscured and high redshift objects inherent in our IRAC-based selection technique.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Lacy, M.0000-0002-3032-1783
Sajina, A.0000-0002-1917-1200
Canalizo, G.0000-0003-4693-6157
Additional Information:© 2006 Astronomical Society of the Pacific. We thank Alejo Martinez-Sansigre and Steve Rawlings for their contributions to the spectroscopic observations.
Series Name:ASP Conference Series
Issue or Number:357
Record Number:CaltechAUTHORS:20110615-134620653
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:24016
Deposited By: Tony Diaz
Deposited On:17 Jun 2011 17:30
Last Modified:07 Nov 2019 15:00

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