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Accession Number N20120013038
Title Kepler Observations of Rapid Optical Variability in Active Galactic Nuclei.
Publication Date 2012
Media Count 6p
Personal Author P. Gandhi R. Edelson R. F. Mushotzky W. H. Baumgartner
Abstract 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.
Keywords 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

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54B - Astronomy & Celestial Mechanics
Corporate Author Goddard Space Flight Center, Greenbelt, MD.
Document Type Journal article
Title Note N/A
NTIS Issue Number 1303
Contract Number N/A

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