Characteristic QSO Accretion Disk Temperatures from Spectroscopic Continuum Variability

Abstract

Using Sloan Digital Sky Survey (SDSS) quasar spectra taken at multiple epochs, we find that the composite flux density differences in the rest frame wavelength range 1300-6000 AA can be fit by a standard thermal accretion disk model where the accretion rate has changed from one epoch to the next (without considering additional continuum emission components). The fit to the composite residual has two free parameters: a normalizing constant and the average characteristic temperature ${\bar{T}}^{\ast }$. In turn the characteristic temperature is dependent on the ratio of the mass accretion rate to the square of the black hole mass. We therefore conclude that most of the UV/optical variability may be due to processes involving the disk, and thus that a significant fraction of the UV/optical spectrum may come directly from the disk.

31 pages, 8 figures

References in corpus (20)

• The Sloan Digital Sky Survey: Technical Summary
• The Sloan Digital Sky Survey Photometric Camera
• The u'g'r'i'z' Standard Star Network
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
• Astrometric Calibration of the Sloan Digital Sky Survey
• Sources of Relativistic Jets in the Galaxy
• The Third Data Release of the Sloan Digital Sky Survey
• A photometricity and extinction monitor at the Apache Point Observatory
• An Efficient Algorithm for Positioning Tiles in the Sloan Digital Sky Survey
• The Ensemble Photometric Variability of ~25000 Quasars in the Sloan Digital Sky Survey
• SDSS Data Management and Photometric Quality Assessment
• The Sloan Digital Sky Survey Quasar Catalog II. First Data Release
• Non-LTE Models and Theoretical Spectra of Accretion Disks in Active Galactic Nuclei. IV. Effects of Compton Scattering and Metal Opacities
• Non-LTE Models and Theoretical Spectra of Accretion Disks in Active Galactic Nuclei. III. Integrated Spectra for Hydrogen-Helium Disks
• Universal spectral shape of high accretion rate AGN
• Spectral Variability of Quasars in the Sloan Digital Sky Survey. I: Wavelength Dependence
• The nature and size of the optical continuum source in QSO 2237+0305
• Constraints on AGN accretion disc viscosity derived from continuum variability
• The Optical-UV Continuum of a Sample of QSOs
• Relation between blue/UV continuum shape and the ratio of radio to optical emission for B3-VLA quasars

Cited by in corpus (68)

• Modeling the Time Variability of SDSS Stripe 82 Quasars as a Damped Random Walk
• PS16dtm: A Tidal Disruption Event in a Narrow-line Seyfert 1 Galaxy
• Selecting Quasars by their Intrinsic Variability
• An X-shooter composite of bright 1 < z < 2 quasars from UV to infrared
• iPTF Discovery of the Rapid "Turn On" of a Luminous Quasar
• On the variability of quasars: a link between Eddington ratio and optical variability?
• Detailed Characterization of H_beta emission line profile in low z SDSS quasars
• Quasar Optical Variability in the Palomar-QUEST Survey
• A new physical interpretation of optical and infrared variability in quasars
• Pan-STARRS1 variability of XMM-COSMOS AGN. II. Physical correlations and power spectrum analysis
• The Color Variability of Quasars
• Spectral variability of quasars from multi-epoch photometric data in the Sloan Digital Sky Survey Stripe 82
• Evidence for Large Temperature Fluctuations in Quasar Accretion Disks From Spectral Variability
• The dependence of quasar variability on black hole mass
• Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies
• An accretion disc model for quasar optical variability
• The Evolution of Quasar CIV and SiIV Broad Absorption Lines Over Multi-Year Time Scales
• The Discovery of Timescale-Dependent Color Variability of Quasars
• Long-Term Optical Continuum Color Variability of Nearby Active Galactic Nuclei
• Examining AGN UV/optical Variability Beyond the Simple Damped Random Walk
• The GALEX Time Domain Survey I. Selection and Classification of Over a Thousand UV Variable Sources
• Measuring Quasar Variability with Pan-STARRS1 and SDSS
• Distinguishing Tidal Disruption Events from Impostors
• GALEX observations of quasar variability in the ultraviolet
• Tests for Standard Accretion Disk Models by Variability in Active Galactic Nuclei
• The Composite Spectrum of BOSS Quasars Selected for Studies of the Lyman-alpha Forest
• Variability-selected Active Galactic Nuclei in the VST-SUDARE/VOICE Survey of the COSMOS Field
• Statistical Properties of Multi-epoch Spectral Variability of SDSS Stripe82 Quasars
• Sifting for Sapphires: Systematic Selection of Tidal Disruption Events in iPTF
• Average Properties of a Large Sample of z_abs ~ z_em associated Mg II Absorption Line Systems
• Simulating the timescale dependent color variation in quasars with a revised inhomogeneous disk model
• A large sample of Kohonen-selected SDSS quasars with weak emission lines: selection effects and statistical properties
• Absorption of 10 Gev--1 Tev Gamma Rays by Radiation from Broad-Line Region in 3C 279
• Ultraviolet variability of quasars: dependence on the accretion rate
• Variability and Multiwavelength Detected AGN in the GOODS Fields
• The optical variability of SDSS quasars from multi-epoch spectroscopy. II. color variation
• Constraints on the temperature inhomogeneity in quasar accretion discs from the ultraviolet-optical spectral variability
• Ultraviolet Continuum Color Variability of Luminous Sloan Digital Sky Survey QSOs
• On inferring extinction laws in z~6 quasars as signatures of supernova dust
• A Search for Synchrotron X-ray Emission in Radio Quasars
• AT 2021loi: A Bowen Fluorescence Flare with a Rebrightening Episode, Occurring in a Previously-Known AGN
• The Ultraviolet/optical variability of steep-spectrum radio quasars: the change in accretion rate ?
• Optical Variability of Infrared Power Law-Selected Galaxies & X-ray Sources in the GOODS-South Field
• Extreme Variability Quasars in Their Various States. I: The sample selection and composite SDSS spectra
• The Timescale-Dependent Color Variability of Quasars Viewed with GALEX
• Probing Spectroscopic Variability of Galaxies & Narrow-Line Active Galactic Nuclei in the Sloan Digital Sky Survey
• I. Flux and color variations of the quadruply imaged quasar HE 0435-1223
• Correlation between Optical and UV Variability of Quasars
• Modeling the Variability of Active Galactic Nuclei by Infinite Mixture of Ornstein-Uhlenbeck(OU) Processes
• MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723 and HE0047-1756: Microlensing and a new time delay
• An Accretion Disc-Irradiation Hybrid Model for The Optical/UV Variability in Radio-Quiet Quasars
• An Unobscured type II quasar candidate: SDSS J012032.19-005501.9
• Broad-band spectral energy distribution of 3000 Angstroem break quasars from the Sloan Digital Sky Survey
• The GALEX Time Domain Survey. II. Wavelength-Dependent Variability of Active Galactic Nuclei in the Pan-STARRS1 Medium Deep Survey
• Individual optical variability of Active Galactic Nuclei from the MEXSAS2 sample
• Selection of AGN candidates in the GOODS-South Field through SPITZER/MIPS 24 $\mu$m variability
• The Relation between X-ray and Ultraviolet Variability of Quasars
• Optical Microvariability in Quasars: Spectral Variability
• Ensemble Variability Properties of Active Galactic Nuclei in the SDSS DR17
• The Spectroscopic Signature of Variability in High-Redshift Quasars
• The relationship between variable and polarized optical spectral components of luminous type 1 non-blazar quasars
• Constraints on the optical polarization source in the luminous non-blazar quasar 3C 323.1 (PG 1545+210) from the photometric and polarimetric variability
• Brightness and colour variability in NLSy1s
• Exploration of the origin of 2020 X-ray outburst in OJ 287
• SDSSJ14584479+3720215: A Benchmark JHK Blazar Light Curve from the 2MASS Calibration Scans
• Decadal Variability Survey in MACSJ1149
• Gaia-supported re-discovery of a remarkable weak line quasar from a variability and proper motion survey
• Exploring the Variable Sky with the Sloan Digital Sky Survey