The Population of High Redshift AGNs in the Chandra COSMOS survey

Abstract

We present the high redshift (3<z<5.3) 0.5-2 keV number counts and the 2-10 keV (rest frame) space density of X-ray selected AGNs detected in the Chandra COSMOS survey. The sample comprises 81 X-ray detected sources with available spectroscopic (31) and photometric (50) redshifts plus 20 sources with a formal z_phot<3 but with a broad photometric redshift probability distribution, such that z_phot+1sigma>3. 81 sources are selected in the 0.5-2 keV band, 14 are selected in the 2-10 keV and 6 in the 0.5-10 keV bands. We sample the high luminosity (log L_(2-10 keV)>44.15 erg/s) space density up to z~5 and a fainter luminosity range (43.5<log L(2-10 keV)<44.15 erg/s) than previous studies, up to z=3.5. We weighted the contribution to the number counts and the space density of the sources with photometric redshift by using their probability of being at z>3. We find that the space density of high-luminosity AGNs declines exponentially at all the redshifts, confirming the trend observed for optically selected quasars. At lower luminosity, the measured space density is not conclusive, and a larger sample of faint sources is needed. Comparisons with optical luminosity functions and BH formation models are presented together with prospects for future surveys.

10 pages, 6 figures. ApJ in press. Table 3 is available in the published version

References in corpus (23)

• zCOSMOS: A Large VLT/VIMOS redshift survey covering 0 < z < 3 in the COSMOS field
• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• The Chandra Deep Field-South Survey: 4 Ms Source Catalogs
• The Chandra COSMOS Survey, I: Overview and Point Source Catalog
• Photometric redshift and classification for the XMM-COSMOS sources
• Absorption Properties and Evolution of Active Galactic Nuclei
• A massive proto-cluster of galaxies at a redshift of z {\approx} 5.3
• The Luminosity Function of X-ray Selected Active Galactic Nuclei: Evolution of Supermassive Black Holes at High Redshift
• The Blast Wave Model for AGN Feedback: Effects on AGN Obscuration
• The XMM-Newton Wide field survey in the COSMOS field: redshift evolution of AGN bias and subdominant role of mergers in triggering moderate luminosity AGN at redshift up to 2.2
• The XMM Deep survey in the CDFS I. First results on heavily obscured AGN
• The Faint End of the Quasar Luminosity Function at z~4: Implications for Ionization of the Intergalactic Medium and Cosmic Downsizing
• Probing the Evolution of IR Properties of z~6 Quasars: Spitzer Observations
• Magellan Spectroscopy of AGN Candidates in the COSMOS Field
• Lyman Alpha Emitters at Redshift 5.7 in the COSMOS Field
• High redshift quasars in the COSMOS survey: the space density of z>3 X-ray selected QSOs
• The XMM-Newton Serendipitous Survey. VI. The X-ray Luminosity Function
• The Luminosity Function of high-redshift QSOs - A combined analysis of GOODS and SDSS
• Supermassive Black Holes in the Hierarchical Universe: A General Framework and Observational Tests
• A Compton-thick AGN at z~5 in the 4 Ms Chandra Deep Field South
• Probing the faint end of the quasar luminosity function at z ~ 4 in the COSMOS field
• Wide Field X-ray Telescope: Mission Overview
• Identification of (high-redshift) AGN with WFXT: lessons from COSMOS and CDFS

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• Cosmic X-ray Surveys of Distant Active Galaxies: The Demographics, Physics, and Ecology of Growing Supermassive Black Holes
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• The 4 Ms Chandra Deep Field-South Number Counts Apportioned by Source Class: Pervasive Active Galactic Nuclei and the Ascent of Normal Galaxies
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• Faint high-redshift AGN in the Chandra Deep Field South: the evolution of the AGN luminosity function and black hole demography
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• Peering through the holes: the far UV color of star-forming galaxies at z~3-4 and the escaping fraction of ionizing radiation
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• The deepest X-ray view of high-redshift galaxies: constraints on low-rate black-hole accretion
• Constraining the UV emissivity of AGN throughout cosmic time via X-ray surveys
• The NuSTAR Extragalactic Surveys: Overview and Catalog from the COSMOS Field
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• Supermassive black holes in cosmological simulations II: the AGN population and predictions for upcoming X-ray missions
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• The Chandra COSMOS Legacy survey: the z>3 sample
• Modelling the luminosities and sizes of radio galaxies: radio luminosity function at z = 6
• Constraints on the faint end of the quasar luminosity function at z~5 in the COSMOS field
• Spectral Energy Distributions of Type 1 AGN in XMM-COSMOS Survey II - Shape Evolution
• The Largest X-ray Selected Sample of z>3 AGNs: C-COSMOS & ChaMP
• AGN and QSOs in the eROSITA All-Sky Survey -- Part I: Statistical properties
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• Highlights and Discoveries from the Chandra X-ray Observatory
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• A Quasar-Galaxy Mixing Diagram: Quasar Spectral Energy Distribution Shapes in the Optical to Near-Infrared
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