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Mid-infrared-selected Quasars. I. Virial Black Hole Mass and Eddington Ratios

Dai, Y. Sophia and Elvis, Martin and Bergeron, Jacqueline and Fazio, Giovanni G. and Huang, Jia-Sheng and Wilkes, Belinda J. and Willmer, Christopher N. A. and Omont, Alain and Papovich, Casey (2014) Mid-infrared-selected Quasars. I. Virial Black Hole Mass and Eddington Ratios. Astrophysical Journal, 791 (2). Art. No. 113. ISSN 0004-637X.

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We provide a catalog of 391 mid-infrared-selected (MIR; 24 μm) broad-emission-line (BEL; type 1) quasars in the 22 deg^2 SWIRE Lockman Hole field. This quasar sample is selected in the MIR from Spitzer MIPS with S_(24) > 400 μJy, jointly with an optical magnitude limit of r (AB) < 22.5 for broad line identification. The catalog is based on MMT and Sloan Digital Sky Survey (SDSS) spectroscopy to select BEL quasars, extending the SDSS coverage to fainter magnitudes and lower redshifts, and recovers a more complete quasar population. The MIR-selected quasar sample peaks at z ~ 1.4 and recovers a significant and constant (20%) fraction of extended objects with SDSS photometry across magnitudes, which were not included in the SDSS quasar survey dominated by point sources. This sample also recovers a significant population of z < 3 quasars at i > 19.1. We then investigate the continuum luminosity and line profiles of these MIR quasars, and estimate their virial black hole masses and the Eddington ratios. The supermassive black hole mass shows evidence of downsizing, although the Eddington ratios remain constant at 1 < z < 4. Compared to point sources in the same redshift range, extended sources at z < 1 show systematically lower Eddington ratios. The catalog and spectra are publicly available online.

Item Type:Article
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URLURL TypeDescription
Dai, Y. Sophia0000-0002-7928-416X
Bergeron, Jacqueline0000-0002-1201-873X
Fazio, Giovanni G.0000-0002-0670-0708
Wilkes, Belinda J.0000-0003-1809-2364
Omont, Alain0000-0002-4721-3922
Additional Information:© 2014 American Astronomical Society. Received 2013 November 5; accepted 2014 June 12; published 2014 August 5. Y.S.D. acknowledges support from the Smithsonian Astrophysical Observatory (SAO) through the SAO Predoctoral Fellowship. We thank the anonymous referee for suggestions that led to the improvement of the manuscript. We thank Yue Shen for sharing the spectral measurement code, and Richard Cool for sharing and supporting of the HSRED reduction code. Observations reported here were obtained at the MMT Observatory, a joint facility of the Smithsonian Institution and the University of Arizona. This work is also based partly on observations made with the Spitzer Space Telescope, operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS Web site is Facilities: MMT, Spitzer, Sloan
Funding AgencyGrant Number
Smithsonian Astrophysical Observatory (SAO)UNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
Participating InstitutionsUNSPECIFIED
Department of Energy (DOE)UNSPECIFIED
Japanese MonbukagakushoUNSPECIFIED
Max Planck SocietyUNSPECIFIED
Higher Education Funding Council for England UNSPECIFIED
Subject Keywords:catalogs; galaxies: active; galaxies: high-redshift; galaxies: Seyfert; infrared: galaxies; quasars: general; quasars: supermassive black holes
Issue or Number:2
Record Number:CaltechAUTHORS:20140904-083629624
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Official Citation:Mid-infrared-selected Quasars. I. Virial Black Hole Mass and Eddington Ratios Y. Sophia Dai (戴昱) et al. 2014 ApJ 791 113
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:49224
Deposited By: Ruth Sustaita
Deposited On:04 Sep 2014 16:15
Last Modified:01 Nov 2019 23:43

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