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Magellan Spectroscopy of AGN Candidates in the COSMOS Field

Jonathan R. Trump·Chris D. Impey·Patrick J. McCarthy·Martin Elvis·John P. Huchra·Marcella Brusa·Gunther Hasinger·Eva Schinnerer·Peter Capak·Simon J. Lilly·Nick Z. Scoville
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Abstract

We present spectroscopic redshifts for the first 466 X-ray and radio-selected AGN targets in the 2 deg^2 COSMOS field. Spectra were obtained with the IMACS instrument on the Magellan (Baade) telescope, using the nod-and-shuffle technique. We identify a variety of Type 1 and Type 2 AGN, as well as red galaxies with no emission lines. Our redshift yield is 72% down to i_AB=24, although the yield is >90% for i_AB<22. We expect the completeness to increase as the survey continues. When our survey is complete and additional redshifts from the zCOSMOS project are included, we anticipate ~1100 AGN with redshifts over the entire COSMOS field. Our redshift survey is consistent with an obscured AGN population that peaks at z~0.7, although further work is necessary to disentangle the selection effects.

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Jonathan R. Trump, Chris D. Impey, Patrick J. McCarthy, Martin Elvis, John P. Huchra, Marcella Brusa, Gunther Hasinger, Eva Schinnerer, Peter Capak, Simon J. Lilly, Nick Z. Scoville. 2006-06-01. Magellan Spectroscopy of AGN Candidates in the COSMOS Field. https://doi.org/10.1086/516578

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