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Accession Number
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N20120013038
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Title
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Kepler Observations of Rapid Optical Variability in Active Galactic Nuclei.
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Publication Date
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2012
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Media Count
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6p
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Personal Author
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P. Gandhi R. Edelson R. F. Mushotzky W. H. Baumgartner
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Abstract
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Over three quarters in 2010 - 2011, Kepler monitored optical emission from four active galactic nuclei (AGN) with approx 30 min sampling, > 90% duty cycle and approx < 0.1% repeatability. These data determined the AGN optical fluctuation power spectral density functions (PSDs) over a wide range in temporal frequency. Fits to these PSDs yielded power law slopes of -2.6 to -3.3, much steeper than typically seen in the X-rays. We find evidence that individual AGN exhibit intrinsically different PSD slopes. The steep PSD fits are a challenge to recent AGN variability models but seem consistent with first order MRI theoretical calculations of accretion disk fluctuations.
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Keywords
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Accretion disks
Active galactic nuclei
Active galaxies
Astronomical photometry
Black holes(Astronomy)
Kepler mission
Light emission
Power spectra
Seyfert galaxies
Space observations(From earth)
Time series analysis
Variability
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Source Agency
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National Aeronautics and Space Administration
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NTIS Subject Category
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54B - Astronomy & Celestial Mechanics
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Corporate Author
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Goddard Space Flight Center, Greenbelt, MD.
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Document Type
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Journal article
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Title Note
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N/A
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NTIS Issue Number
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1303
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Contract Number
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N/A
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