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Burke CJ, Shen Y, Blaes O, Gammie CF, Horne K, Jiang YF, Liu X, McHardy IM, Morgan CW, Scaringi S, Yang Q. A characteristic optical variability time scale in astrophysical accretion disks. Science 2021; 373:789-792. [PMID: 34385395 DOI: 10.1126/science.abg9933] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/11/2021] [Indexed: 12/30/2022]
Abstract
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.
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Affiliation(s)
- Colin J Burke
- Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,Center for AstroPhysical Surveys, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yue Shen
- Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. .,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Omer Blaes
- Department of Physics, University of California, Santa Barbara, CA 93106, USA
| | - Charles F Gammie
- Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,Illinois Center for Advanced Study of the Universe, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Keith Horne
- School of Physics and Astronomy, University of St. Andrews, Fife KY16 9SS, UK
| | - Yan-Fei Jiang
- Center for Computational Astrophysics, Flatiron Institute, New York, NY 10010, USA
| | - Xin Liu
- Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ian M McHardy
- Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK
| | | | - Simone Scaringi
- Department of Physics, University of Durham, Durham DH1 3LE, UK
| | - Qian Yang
- Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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2
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Kraus S, Kreplin A, Young AK, Bate MR, Monnier JD, Harries TJ, Avenhaus H, Kluska J, Laws ASE, Rich EA, Willson M, Aarnio AN, Adams FC, Andrews SM, Anugu N, Bae J, Ten Brummelaar T, Calvet N, Curé M, Davies CL, Ennis J, Espaillat C, Gardner T, Hartmann L, Hinkley S, Labdon A, Lanthermann C, LeBouquin JB, Schaefer GH, Setterholm BR, Wilner D, Zhu Z. A triple-star system with a misaligned and warped circumstellar disk shaped by disk tearing. Science 2020; 369:1233-1238. [PMID: 32883866 DOI: 10.1126/science.aba4633] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 07/24/2020] [Indexed: 11/02/2022]
Abstract
Young stars are surrounded by a circumstellar disk of gas and dust, within which planet formation can occur. Gravitational forces in multiple star systems can disrupt the disk. Theoretical models predict that if the disk is misaligned with the orbital plane of the stars, the disk should warp and break into precessing rings, a phenomenon known as disk tearing. We present observations of the triple-star system GW Orionis, finding evidence for disk tearing. Our images show an eccentric ring that is misaligned with the orbital planes and the outer disk. The ring casts shadows on a strongly warped intermediate region of the disk. If planets can form within the warped disk, disk tearing could provide a mechanism for forming wide-separation planets on oblique orbits.
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Affiliation(s)
- Stefan Kraus
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK.
| | - Alexander Kreplin
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - Alison K Young
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK.,School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - Matthew R Bate
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - John D Monnier
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tim J Harries
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | | | - Jacques Kluska
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK.,Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, 3001 Leuven, Belgium
| | - Anna S E Laws
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - Evan A Rich
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Matthew Willson
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK.,Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30302, USA
| | - Alicia N Aarnio
- Department of Physics and Astronomy, University of North Carolina Greensboro, Greensboro, NC 27402, USA
| | - Fred C Adams
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sean M Andrews
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA 02138, USA
| | - Narsireddy Anugu
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK.,Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA.,Steward Observatory, University of Arizona, Tucson, AZ 85721, USA
| | - Jaehan Bae
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA.,Carnegie Institution for Science, Washington, DC 20015, USA
| | - Theo Ten Brummelaar
- The Center for High Angular Resolution Astronomy Array of Georgia State University, Mount Wilson, CA 91023, USA
| | - Nuria Calvet
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michel Curé
- Instituto de Fisica y Astronomia, Universidad de Valparaiso, Casilla 5030, Valparaiso, Chile
| | - Claire L Davies
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - Jacob Ennis
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Tyler Gardner
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Lee Hartmann
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sasha Hinkley
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - Aaron Labdon
- School of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, UK
| | - Cyprien Lanthermann
- Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, 3001 Leuven, Belgium
| | - Jean-Baptiste LeBouquin
- Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA.,Université Grenoble Alpes, Institut de Planétologie et d'Astrophysique, 38000 Grenoble, France
| | - Gail H Schaefer
- The Center for High Angular Resolution Astronomy Array of Georgia State University, Mount Wilson, CA 91023, USA
| | | | - David Wilner
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA 02138, USA
| | - Zhaohuan Zhu
- Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154, USA
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