The SOUX AGN Sample: SDSS-XMM-Newton Optical, Ultraviolet and X-ray selected active galactic nuclei spanning a wide range of parameter space -- Sample definition

Abstract

We assemble a sample of 696 type 1 AGN up to a redshift of $z=2.5$, all of which have an SDSS spectrum containing at least one broad emission line (H $\alpha$, H $\beta$ or Mg II) and an XMM-Newton X-ray spectrum containing at least 250 counts in addition to simultaneous optical/ultraviolet photometry from the XMM Optical Monitor. Our sample includes quasars and narrow-line Seyfert 1s: thus our AGN span a wide range in luminosity, black hole mass and accretion rate. We determine single-epoch black hole mass relations for the three emission lines and find that they provide broadly consistent mass estimates whether the continuum or emission line luminosity is used as the proxy for the broad emission line region radius. We explore variations of the UV/X-ray energy index ${\alpha }_{\mathrm{ox}}$ with the UV continuum luminosity and with black hole mass and accretion rate, and make comparisons to the physical quasar spectral energy distribution (SED) model QSOSED. The majority of the AGN in our sample lie in a region of parameter space with $0.02<L/L_{\mathrm{Edd}}<2$ as defined by this model, with narrow-line type 1 AGN offset to lower masses and higher accretion rates than typical broad-line quasars. We find differences in the dependence of ${\alpha }_{\mathrm{ox}}$ on UV luminosity between both narrow/broad-line and radio-loud/quiet subsets of AGN: ${\alpha }_{\mathrm{ox}}$ has a slightly weaker dependence on UV luminosity for broad-line AGN and radio-loud AGN have systematically harder ${\alpha }_{\mathrm{ox}}$.

arXiv comment23 pages, 24 figures and 10 tables. Accepted for publication in MNRAS

References in corpus (72)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Astropy: A Community Python Package for Astronomy
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections
• Correcting for the Effects of Interstellar Extinction
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• A Catalog of Quasar Properties from SDSS DR7
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• Towards a unified model for black hole X-ray binary jets
• Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
• A fundamental plane of black hole activity
• Estimating Black Hole Masses in Active Galaxies Using the Halpha Emission Line
• astroquery: An Astronomical Web-Querying Package in Python
• Intrinsic disc emission and the Soft X-ray Excess in AGN
• The Sloan Digital Sky Survey Quasar Catalog: Fourteenth Data Release
• Is the soft excess in AGN real?
• The X-ray to optical-UV luminosity ratio of X-ray selected Type 1 AGN in XMM-COSMOS
• The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements
• The XMM-Newton serendipitous survey IX. The fourth XMM-Newton serendipitous source catalogue
• A Comprehensive Study of 2 000 Narrow Line Seyfert 1 Galaxies from the Sloan Digital Sky Survey: I. The Sample
• Radio-loud Narrow-Line Type 1 Quasars
• Comparing Single-Epoch Virial Black Hole Mass Estimators for Luminous Quasars
• Spectral Classification of Quasars in the Sloan Digital Sky Survey: Eigenspectra; Redshift and Luminosity Effects
• A physical model of the broadband continuum of AGN and its implications for the UV/X relation and optical variability
• Explaining changing-look AGN with state transition triggered by rapid mass accretion rate drop
• Soft X-ray and Ultraviolet Emission Relations in Optically Selected AGN Samples
• The tight relation between X-ray and ultraviolet luminosity of quasars
• Spectral properties of quasars from Sloan Digital Sky Survey data release 14: The catalog
• Accretion states and radio loudness in Active Galactic Nuclei: analogies with X-ray binaries
• Broad-line Balmer Decrements in Blue Active Galactic Nuclei
• Distributions of Galaxy Spectral Types in the Sloan Digital Sky Survey
• The Sloan Digital Sky Survey Reverberation Mapping Project: Sample Characterization
• A Combined Optical and X-ray Study of Unobscured Type 1 AGN. I. Optical Spectra and SED Modeling
• The Chandra Deep Field-North Survey. XIV. X-ray detected Obscured AGNs and Starburst Galaxies in the Bright Submm Source Population
• The Nuclear Reddening Curve for Active Galactic Nuclei and the Shape of the Infra-Red to X-Ray Spectral Energy Distribution
• Bolometric correction factors for Active Galactic Nuclei
• Mean Spectral Energy Distributions and Bolometric Corrections for Luminous Quasars
• A combined Optical and X-ray Spectra Study for Type 1 AGN. III. Broadband SED Properties
• A Catalog of Narrow Line Seyfert 1 Galaxies from the Sloan Digital Sky Survey Data Release 12
• Black-Hole Mass and Growth Rate at High Redshift
• Active galactic nuclei at z~1.5: II. Black Hole Mass estimation by means of broad emission lines
• Quasars as standard candles I: The physical relation between disc and coronal emission
• The XMM-Newton serendipitous ultraviolet source survey catalogue
• The Analogous Structure of Accretion Flows in Supermassive and Stellar Mass Black Holes: New Insights from Faded Changing-Look Quasars
• The near-infrared broad emission line region of active galactic nuclei. II. The one-micron continuum
• Constraining Sub-Parsec Binary Supermassive Black Holes in Quasars with Multi-Epoch Spectroscopy. III. Candidates from Continued Radial Velocity Tests
• A Combined Optical and X-ray Study of Unobscured Type 1 AGN. II. Relation Between X-ray Emission and Optical Spectra
• QSFit: Automatic analysis of optical AGN spectra
• The case for cases B and C: intrinsic hydrogen line ratios of the broad-line region of active galactic nuclei, reddenings, and accretion disc sizes
• The Lick AGN Monitoring Project: Alternate Routes to a Broad-line Region Radius
• Quasars as standard candles II: The non linear relation between UV and X-ray emission at high redshifts
• The $L_{\mathrm{x}}$-$L_{\mathrm{uv}}$-$L_{\mathrm{radio}}$ relation and corona-disk-jet connection in optically selected radio-loud quasars
• The Sloan Digital Sky Survey Reverberation Mapping Project: Ensemble Spectroscopic Variability of Quasar Broad Emission Lines
• Understanding Broad Mg II Variability in Quasars with Photoionization: Implications for Reverberation Mapping and Changing-Look Quasars
• Modelling the spectral energy distribution of super-Eddington quasars
• Constraints on the Broad Line Region Properties and Extinction in Local Seyferts
• Calibration and Limitations of the Mg II line-based Black Hole Masses
• On the black hole mass of the gamma-ray emitting narrow-line Seyfert 1 galaxy 1H 0323+342
• AGN spectral states from simultaneous UV and X-ray observations by XMM-Newton
• X-ray binary accretion states in Active Galactic Nuclei? Sensing the accretion disc of supermassive black holes with mid-infrared nebular lines
• Reddening of the BLR and NLR in AGN From a Systematic Analysis of Balmer Decrement
• Quasars as high-redshift standard candles
• The near-infrared radius-luminosity relationship for active galactic nuclei
• Reaching the Peak of the quasar spectral energy distribution - II. Exploring the accretion disc, dusty torus and host galaxy
• Reaching the Peak of the Quasar Spectral Energy Distribution I: Observations and Models
• Relation between the variations in the MgII $\lambda 2798$ emission-line and the 3000 Å continuum
• The relativistic jet of the $\gamma$-ray emitting narrow-line Seyfert 1 galaxy PKS J1222$+$0413
• Do stellar-mass and super-massive black holes have similar dining habits?
• The 'Big Dipper': The nature of the extreme variability of the AGN SDSS J2232-0806
• A catalog of optical to X-ray spectral energy distributions of z~2 quasars observed with Swift. I: First results

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