A population of Optically Quiescent Quasars from WISE and SDSS

Abstract

The growth of active galactic nuclei (AGN) occurs under some form of obscuration in a large fraction of the population. The difficulty in constraining this population leads to high uncertainties in cosmic X-ray background and galaxy evolution models. Using an SDSS-WISE cross-match, we target infrared luminous AGN ($W1-W2$ > 0.8, and monochromatic rest-frame luminosity above $\lambda L_{\lambda }$(12$\mu$m) $\approx$ 3 $\times$ 10${}^{44}$ erg s${}^{-1}$), but with passive galaxy-like optical spectra (Optically Quiescent Quasars; OQQs). We find 47 objects that show no significant [O III]$\lambda$5007 emission, a typically strong AGN optical emission line. As a comparison sample, we examine SDSS-selected Type 2 quasars (QSO2s), which show a significant [O III]$\lambda$5007 line by definition. We find a 1:16 ratio of OQQs compared to QSO2s, suggesting that the OQQ duty cycle is likely much shorter than that of QSO2s (though selection biases are not fully quantified). We consider observed properties in comparison with other galaxy types, and examine them for consistency with theories on their intrinsic nature: chiefly (a) a high covering factor for surrounding obscuring matter, preventing the detection of high-ionisation emission lines - `cocooned AGN'; or (b) ionised gas being absent on the kpc scales of the Narrow Line Region (NLR), perhaps due to a `switching on' or `young' AGN. OQQs do not obviously fit the standard paradigm for merger-driven AGN and host galaxy evolution, implying we may be missing part of the flow of AGN evolution.

Accepted for publication in MNRAS (20 pages, 18 figures)

References in corpus (50)

• The Host Galaxies and Classification of Active Galactic Nuclei
• A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies: I. Galaxy Mergers & Quasar Activity
• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• Toward the Standard Population Synthesis Model of the X-Ray Background: Evolution of X-Ray Luminosity and Absorption Functions of Active Galactic Nuclei Including Compton-Thick Populations
• Distant Radio Galaxies and their Environments
• The diversity of quasars unified by accretion and orientation
• The CatWISE2020 Catalog
• A Significant Population of Very Luminous Dust-Obscured Galaxies at Redshift z ~ 2
• Dust covering factor, silicate emission and star formation in luminous QSOs
• Stellar Masses and SFRs for 1M Galaxies from SDSS and WISE
• The WISE AGN Catalog
• A massive quiescent galaxy at redshift 4.658
• Half of the Most Luminous Quasars May Be Obscured: Investigating the Nature of WISE-Selected Hot, Dust-Obscured Galaxies
• The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
• The distribution of silicate strength in Spitzer spectra of AGNs and ULIRGs
• Suzaku Observations of Active Galactic Nuclei Detected in the Swift/BAT Survey: Discovery of "New Type" of Buried Supermassive Black Holes
• X-ray Insights into the Nature of PHL 1811 Analogs and Weak Emission-Line Quasars: Unification with a Geometrically Thick Accretion Disk?
• A Spitzer IRS Low-Resolution Spectroscopic Search for Buried AGNs in Nearby Ultraluminous Infrared Galaxies - A Constraint on Geometry between Energy Sources and Dust -
• The FIRST-2MASS Red Quasar Survey
• Mid-infrared variability of changing-look AGN
• iPTF Discovery of the Rapid "Turn On" of a Luminous Quasar
• The X-Ray to Mid-Infrared Relation of AGN at High Luminosity
• The WISE Blazar-Like Radio-Loud Sources: An All-Sky Catalog Of Candidate Gamma-Ray Blazars
• Incidence of WISE-Selected Obscured AGNs in Major Mergers and Interactions from the SDSS
• The Correlation of Narrow Line Emission and X-ray Luminosity in Active Galactic Nuclei
• High redshift quasars in the COSMOS survey: the space density of z>3 X-ray selected QSOs
• Heavily reddened type 1 quasars at z > 2 I: Evidence for significant obscured black-hole growth at the highest quasar luminosities
• A hard X-ray view of Luminous and Ultra-luminous Infrared Galaxies in GOALS: I - AGN obscuration along the merger sequence
• Buried AGNs in Advanced Mergers:Mid-infrared color selection as a dual AGN finder
• Luminosity and Redshift Dependence of the Covering Factor of AGNs viewed with WISE and SDSS
• A dust-parallax distance of 19 megaparsecs to the supermassive black hole in NGC 4151
• Elusive AGN in the XMM-Newton bright serendipitous survey
• The NuSTAR Serendipitous Survey: Hunting for The Most Extreme Obscured AGN at >10 keV
• The HELLAS2XMM survey.VIII. Optical identifications of the extended sample
• The HELLAS2XMM survey: XI. Unveiling the nature of X-ray Bright Optically Normal Galaxies
• The quest for Type 2 quasars: Chandra observations of luminous obscured quasars in the Sloan Digital Sky Survey
• A large sample of Kohonen-selected SDSS quasars with weak emission lines: selection effects and statistical properties
• Emission Line Properties of Seyfert Galaxies in the 12 Micron Sample
• BAT AGN Spectroscopic Survey XXVII: Scattered X-Ray Radiation in Obscured Active Galactic Nuclei
• A Spectroscopic Survey of WISE-selected Obscured Quasars with the Southern African Large Telescope
• An Infrared and Optical Analysis of a Sample of XBONGs and Optically Elusive AGN
• The WISE-2MASS Survey: Red Quasars Into the Radio Quiet Regime
• Detection of faint broad emission lines in type 2 AGN: I. Near infrared observations and spectral fitting
• $NuSTAR$ Observations of Four Nearby X-ray Faint AGN: Low Luminosity or Heavy Obscuration?
• Imaging Polarization of the Blue-Excess Hot Dust-Obscured Galaxy WISE J011601.41-050504.0
• NuSTAR Observations of AGN with Low Observed X-ray to [OIII] Luminosity Ratios: Heavily Obscured AGN or Turned-Off AGN?
• 4C 39.29 - extended emission around a powerful Type 2 quasar
• Characterizing the WISE-selected Heavily Obscured Quasar Population with Optical Spectroscopy from the Southern African Large Telescope
• A candidate Optically Quiescent Quasar lacking narrow emission lines
• XMM-Newton and NuSTAR Observations of an Optically Quiescent Quasar

Cited by in corpus (1)

• Unveiling the Dark Side of UV/Optical Bright Galaxies: Optically Thick Dust Absorption