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Cited by 486Galaxies: Formation, Evolution, PhenomenaAstrophysical Phenomena and ObservationsStellar, planetary, and galactic studies

The Ensemble Photometric Variability of ∼25,000 Quasars in the Sloan Digital Sky Survey

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Vanden Berk, Daniel E., Wilhite, Brian C., Kron, Richard G., Anderson, Scott F., Brunner, Robert J., Hall, Patrick B., Ivezić, Željko, Richards, Gordon T. +6 more·2004·The Astrophysical Journal
DOI 10.1086/380563
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Abstract

Using a sample of over 25,000 spectroscopically confirmed quasars from the Sloan Digital Sky Survey, we show how quasar variability in the rest-frame optical/UV regime depends on rest-frame time lag, luminosity, rest wavelength, redshift, the presence of radio and X-ray emission, and the presence of broad absorption line systems. Imaging photometry is compared with three-band spectrophotometry obtained at later epochs spanning time lags up to about 2 yr. The large sample size and wide range of parameter values allow the dependence of variability to be isolated as a function of many independent parameters. The time dependence of variability (the structure function) is well fitted by a single power law with an index γ = 0.246 ± 0.008, on timescales from days to years. There is an anticorrelation of variability amplitude with rest wavelength—e.g., quasars are about twice as variable at 1000 Å as at 6000 Å—and quasars are systematically bluer when brighter at all redshifts. There is a strong anticorrelation of variability with quasar luminosity—variability amplitude decreases by a factor of about 4 when luminosity increases by a factor of 100. There is also a significant positive correlation of variability amplitude with redshift, indicating evolution of the quasar population or the variability mechanism. We parameterize all of these relationships. Quasars with ROSAT All-Sky Survey X-ray detections are significantly more variable (at optical/UV wavelengths) than those without, and radio-loud quasars are marginally more variable than their radio-quiet counterparts. We find no significant difference in the variability of quasars with and without broad absorption line troughs. Currently, no models of quasar variability address more than a few of these relationships. Models involving multiple discrete events or gravitational microlensing are unlikely by themselves to account for the data. So-called accretion disk instability models are promising, but more quantitative predictions are needed.

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  • LSST will enable studies of quasar variability using accurate multicolor light curves for a few million quasars, constraining accretion physics and nuclear environments.

    “A study of quasar variability using accurate, multicolor light curves for a few million quasars, leading to constraints on the accretion physics and nuclear environments”

    From LSST: From Science Drivers to Reference Design and Anticipated Data Products (2019) · cites this paper as Vanden Berk et al. 2004

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Research works printed but not linked: 2

  1. Lupton, R., Gunn, J. E., Ivezic ´, Z ˇ., Knapp, G. R., Kent, S., & Yasuda, N. 2001, in ASP Conf. Ser. 238, Astronomical Data Analysis Software and Systems X, ed. F. R. Harnden, Jr., F. A. Primini, & H. E. Payne (San Francisco: ASP), 269
  2. Peterson, B. M. 2001, in Advanced Lectures on the Starburst-AGN Connection, ed. I. Aretxaga, D. Kunth, & R. Mu ´jica (Singapore: World Scientific), 3

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Authors
Vanden Berk, D. E., Wilhite, B. C., Kron, R. G., Anderson, S. F., Brunner, R. J., Hall, P. B., Ivezić, Ž., Richards, G. T., Schneider, D. P., York, D. G., Brinkmann, J. V., Lamb, D. Q., Nichol, R. C., & Schlegel, D. J.
Affiliations
  • Fermi National Accelerator Laboratory (US)
  • University of Washington (US)
  • University of Illinois Urbana-Champaign (US)
  • Pontificia Universidad Católica de Chile (CL)
  • Princeton University (US)
  • Pennsylvania State University (US)
  • University of Chicago (US)
  • Carnegie Mellon University (US)
ORCID
Venue
The Astrophysical Journal
Publisher
American Astronomical Society
Published
2004-02
Volume
601
Issue
2
Pages
692-714
ISSN
  • 0004-637X (ISSN-L)
  • 1538-4357
DOI
10.1086/380563
OpenAlex
W1985786875
Cited by
486
References
78
Citations by year
2026: 15 · 2025: 38 · 2024: 32 · 2023: 19 · 2022: 16 · 2021: 15 · 2020: 25 · 2019: 13 · 2018: 26 · 2017: 20 · 2016: 42 · 2015: 20 · 2014: 22 · 2013: 25 · 2012: 20
FWCI
11.60
Type
journal article
Language
en
Open access
Locations
  • The Astrophysical Journal (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • arXiv (Cornell University)
Funders
  • National Science Foundation
  • U.S. Department of Energy
  • National Aeronautics and Space Administration
  • Alfred P. Sloan Foundation
  • Princeton University
  • University of Washington
  • Johns Hopkins University
  • University of Pittsburgh
  • New Mexico State University
  • Max-Planck-Gesellschaft
  • Max-Planck-Institut für Astronomie
  • U.S. Naval Observatory
  • Fermilab
  • Los Alamos National Laboratory
Topics
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Galaxies: Formation, Evolution, Phenomena
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astrophysical Phenomena and Observations
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Stellar, planetary, and galactic studies
Keywords
quasar variability, photometric variability, structure functions, variability amplitude, quasar luminosity, redshift evolution, X-ray emission, radio-loud quasars, accretion disk instabilities, gravitational microlensing

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