Magellan Spectroscopy of Agn Candidates in the Cosmos Field

Abstract

We present spectroscopic redshifts for the first 466 X-rayY and radio-selected AGN targets in the 2 deg COSMOS field. Spectra were obtained with the IMACS instrument on theMagellan (Baade) telescope, using the nod-and-shuffle technique. We identify a variety of type 1 and type 2 AGNs, as well as red galaxies with no emission lines. Our redshift yield is 72% down to iAB 1⁄4 24, although the yield is >90% for iAB < 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 AGNs 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. Subject headingg s: galaxies: active — quasars: general — surveys Online material: color figures, machine-readable table

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Cite this paper

@inproceedings{Trump2006MagellanSO, title={Magellan Spectroscopy of Agn Candidates in the Cosmos Field}, author={Jonathan R. Trump and Chris D. Impey and Patrick J McCarthy and Martin S. Elvis and John P . Huchra and Marcella Brusa and Gunther Hasinger and Eva Schinnerer and Peter L. Capak and Simon J. Lilly and Nick Z. Scoville}, year={2006} }