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arXiv · 1111.0672

Kepler Observations of Rapid Optical Variability in Active Galactic Nuclei

Richard F. Mushotzky·Rick Edelson·Wayne H. Baumgartner·Poshak Gandhi
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Abstract

Over three quarters in 2010-2011, Kepler monitored optical emission from four active galactic nuclei (AGN) with ~30 min sampling, >90% duty cycle, and <~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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Richard F. Mushotzky, Rick Edelson, Wayne H. Baumgartner, Poshak Gandhi. 2011-11-02. Kepler Observations of Rapid Optical Variability in Active Galactic Nuclei. https://doi.org/10.1088/2041-8205%2F743%2F1%2Fl12

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