Spectral Energy Distribution Variations of Nearby Seyfert Galaxies During AGN Watch Monitoring Programs
arXiv:1710.07051 · doi:10.1093/mnras/stx2689
Abstract
We present and analyse quasi-simultaneous multi-epoch spectral energy distributions (SEDs) of seven reverberation-mapped AGNs for which accurate black hole mass measurements and suitable archival data are available from the 'AGN Watch' monitoring programs. We explore the potential of optical-UV and X-ray data, obtained within 2 days, to provide more accurate SED-based measurements of individual AGN and quantify the impact of source variability on key measurements typically used to characterise the black hole accretion process plus on bolometric correction factors at 5100 Å, 1350 Å and for the 2-10 keV X-ray band, respectively. The largest SED changes occur on long timescales (>1 year). For our small sample, the 1 micron to 10 keV integrated accretion luminosity typically changes by 10% on short time-scales (over 20 days), by ~30% over a year, but can change by 100% or more for individual AGN. The EUV gap is the most uncertain part of the intrinsic SED, introducing a ~25% uncertainty in the accretion-induced luminosity, relative to the model independent interpolation method that we adopt. That aside, our analysis shows that the uncertainty in the accretion-induced luminosity, the Eddington luminosity ratio and the bolometric correction factors can be reduced (by a factor of two or more) by use of SEDs built from data obtained within 20 days. However, mass accretion rate and mass accretion efficiency are mostly limited by the unknown EUV emission and the unknown details of the central engine and our aspect angle.
arXiv commentAccepted for publication in MNRAS, 44 pages, 16 figures, updated with additional literature references and a corrected referencing to databases
References in corpus (102)
- Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
- Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
- Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
- Local Supermassive Black Holes, Relics of Active Galactic Nuclei and the X-ray Background
- Some Aspects of Measurement Error in Linear Regression of Astronomical Data
- Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
- Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
- A Cosmology Calculator for the World Wide Web
- The Low-Luminosity End of the Radius-Luminosity Relationship for Active Galactic Nuclei
- Estimating Black Hole Masses in Active Galaxies Using the Halpha Emission Line
- The Relationship Between Luminosity and Broad-Line Region Size in Active Galactic Nuclei
- Supermassive Black Holes in Active Galactic Nuclei. II. Calibration of the M-sigma Relationship for AGNs
- Intrinsic disc emission and the Soft X-ray Excess in AGN
- The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements II. The Full Sample of Reverberation-Mapped AGNs
- The Rest-Frame Extreme Ultraviolet Spectral Properties of QSOs
- The Soft X-Ray Properties of a Complete Sample of Optically Selected Quasars II. Final Results
- Broad iron lines in Active Galactic Nuclei
- The Ensemble Photometric Variability of ~25000 Quasars in the Sloan Digital Sky Survey
- Piecing Together the X-ray Background: Bolometric Corrections for Active Galactic Nuclei
- A Composite HST Spectrum of Quasars
- Radiation mechanisms and geometry of Cygnus X-1 in the soft state
- Reverberation Measurements of the Inner Radius of the Dust Torus in Nearby Seyfert 1 Galaxies
- Systematic Effects in Measurement of Black Hole Masses by Emission-Line Reverberation of Active Galactic Nuclei: Eddington Ratio and Inclination
- The Lick AGN Monitoring Project: Broad-Line Region Radii and Black Hole Masses from Reverberation Mapping of Hbeta
- Measuring the black hole masses of high redshift quasars
- Black Hole Masses and Eddington Ratios at 0.3<z<4
- An expanded M_bh-sigma diagram, and a new calibration of active galactic nuclei masses
- Determining Central Black Hole Masses in Distant Active Galaxies
- Mass Functions of the Active Black Holes in Distant Quasars from the Large Bright Quasar Survey, the Bright Quasar Survey, and the Color-Selected Sample of the SDSS Fall Equatorial Stripe
- Simultaneous X-ray/optical/UV snapshots of active galactic nuclei from XMM-Newton: spectral energy distributions for the reverberation mapped sample
- Keplerian Motion of Broad-Line Region Gas as Evidence for Supermassive Black Holes in Active Galactic Nuclei
- The AGN Black Hole Mass Database
- Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies
- Multiwavelength Monitoring of the Dwarf Seyfert 1 Galaxy NGC 4395. I. A Reverberation-Based Measurement of the Black Hole Mass
- The Radiative Efficiency of Accretion Flows in Individual AGN
- Space Telescope and Optical Reverberation Mapping Project. III. Optical Continuum Emission and Broad-Band Time Delays in NGC 5548
- Space Telescope and Optical Reverberation Mapping Project. II. Swift and HST Reverberation Mapping of the Accretion Disk of NGC 5548
- Modeling reverberation mapping data II: dynamical modeling of the Lick AGN Monitoring Project 2008 dataset
- Evidence for Supermassive Black Holes in Active Galactic Nuclei from Emission-Line Reverberation
- The Simultaneous Optical-to-X-ray Spectral Energy Distribution of Soft X-ray Selected AGN observed by Swift
- The Black Hole-Bulge Relationship in QSOs
- The New Generation Atlas of Quasar Spectral Energy Distributions from Radio to X-rays
- Black hole masses and enrichment of z ~ 6 SDSS quasars
- Stellar Velocity Dispersion Measurements in High-Luminosity Quasar Hosts and Implications for the AGN Black Hole Mass Scale
- Reverberation Mapping Results for Five Seyfert 1 Galaxies
- An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines
- A Reverberation-Based Mass for the Central Black Hole in NGC 4151
- M-BH - sigma relation for a Complete Sample of Soft X-ray Selected AGNs
- The Lick AGN Monitoring Project: Reverberation Mapping of Optical Hydrogen and Helium Recombination Lines
- Early Growth and Efficient Accretion of Massive Black Holes at High Redshift
- Steps Toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XVI. A Thirteen-Year Study of Spectral Variability in NGC 5548
- The Structure of the Broad Line Region in AGN: I. Reconstructed Velocity-Delay Maps
- A Combined Optical and X-ray Study of Unobscured Type 1 AGN. I. Optical Spectra and SED Modeling
- Anatomy of the AGN in NGC 5548: I. A global model for the broadband spectral energy distribution
- High-Resolution X-ray Spectroscopy and Modeling of the Absorbing and Emitting Outflow in NGC 3783
- Non-LTE Models and Theoretical Spectra of Accretion Disks in Active Galactic Nuclei. IV. Effects of Compton Scattering and Metal Opacities
- Accretion disk wind in the AGN broad-line region: Spectroscopically resolved line profile variations in Mrk110
- Comparing and calibrating black hole mass estimators for distant active galactic nuclei
- Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope
- Multiwavelength campaign on Mrk 509. IV. Optical-UV-X-ray variability and the nature of the soft X-ray excess
- A new cosmological distance measure using AGN
- Swift monitoring of NGC 4151: Evidence for a Second X-ray/UV Reprocessing
- HST-COS Observations of AGN. II. Extended Survey of Ultraviolet Composite Spectra from 159 Active Galactic Nuclei
- The origin of the UV/optical lags in NGC 5548
- The Origin of the X-ray and Ultraviolet Emission in NGC 7469
- The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping
- The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability
- Mass Functions of the Active Black Holes in Distant Quasars from the Sloan Digital Sky Survey Data Release 3
- Optical--to--X-ray emission in low-absorption AGN: Results from the Swift-BAT 9 month catalogue
- Steps toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XII. Ground-Based Monitoring of 3C 390.3
- Dust-free quasars in the early Universe
- Multiwavelength observations of short time-scale variability in NGC 4151. II. Optical observations
- NGC 5548 in a Low-Luminosity State: Implications for the Broad-Line Region
- Probing the interstellar medium and star formation of the Most Luminous Quasar at z=6.3
- Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. VI. Variability of NGC 3783 from ground-based data
- The near-infrared broad emission line region of active galactic nuclei. II. The one-micron continuum
- Active galactic nuclei at gamma-ray energies
- Spectral Energy Distributions of Type 1 AGN in the COSMOS Survey I - The XMM-COSMOS Sample
- Multiwavelength Monitoring of the Narrow-Line Seyfert 1 Galaxy Akn 564. I. ASCA Observations and the Variability of the X-ray Spectral Components
- Calibrating CIV-based black hole mass estimators
- Multiwavelength observations of short time-scale variability in NGC 4151. I. Ultraviolet observations
- Multiwavelength Monitoring of the Narrow-Line Seyfert 1 Galaxy Akn 564. II. Ultraviolet Continuum and Emission-line Variability
- Do the Broad Emission Line Clouds See the Same Continuum that We See?
- Can we measure the accretion efficiency of Active Galactic Nuclei?
- Multiwavelength Monitoring of the Narrow-Line Seyfert 1 Galaxy Akn 564. III. Optical Observations and the Optical--UV--X-ray Connection
- Hard X-ray spectra of AGN in the INTEGRAL complete sample
- Optical Monitoring of the Broad-Line Radio Galaxy 3C390.3
- Simulations of the OzDES AGN Reverberation Mapping Project
- Updating quasar bolometric luminosity corrections. II. Infrared bolometric corrections
- The Origin of UV-optical Variability in AGN and Test of Disc Models: XMM-Newton and ground based observations of NGC4395
- The Mass of the Central Black Hole in the Nearby Seyfert Galaxy NGC5273
- Multiwavelength observations of short time-scale variability in NGC 4151. III. X-ray and Gamma-ray observations
- On the Scatter in the Radius - Luminosity Relationship for Active Galactic Nuclei
- Intrinsic Absorption in the Spectrum of NGC 7469: Simultaneous Chandra, FUSE, and STIS Observations
- Black hole growth by accretion
- Evidence for Nonlinear X-ray Variability from the Broad-line Radio Galaxy 3C 390.3
- Swift/UVOT grism monitoring of NGC 5548 in 2013: an attempt at MgII reverberation mapping
- Multiwavelength XMM-Newton observations of the Laor et al. sample of PG quasars
- High Redshift Standard Candles: Predicted Cosmological Constraints
- Multiwavelength studies of the Seyfert 1 galaxy NGC7469. I - Far UV observations with FUSE
- A Physical Model for the X-ray Time Lags of Narrow Line Seyfert Type 1 Active Galactic Nuclei
- HST-COS Observations of AGNs. III. Spectral Constraints in the Lyman Continuum from Composite COS/G140L Data