A characteristic optical variability time scale in astrophysical accretion disks

Colin J. Burke, Yue Shen*, Omer Blaes, Charles F. Gammie, Keith Horne, Yan-Fei Jiang, Xin Liu, Ian M. McHardy, Christopher W. Morgan, Simone Scaringi, Qian Yang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

63 Citations (Scopus)
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Accretion disks around supermassive black holes in active galactic nuclei produce continuum radiation at ultraviolet and optical wavelengths. Physical processes in the accretion flow lead to stochastic variability of this emission on a wide range of time scales. We measured the optical continuum variability observed in 67 active galactic nuclei and the characteristic time scale at which the variability power spectrum flattens. We found a correlation between this time scale and the black hole mass extending over the entire mass range of supermassive black holes. This time scale is consistent with the expected thermal time scale at the ultraviolet-emitting radius in standard accretion disk theory. Accreting white dwarfs lie close to this correlation, suggesting a common process for all accretion disks.
Original languageEnglish
Pages (from-to)789-792
Number of pages4
Issue number6556
Publication statusPublished - 13 Aug 2021


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