Active Galactic Nuclei Discovered in the Kepler Mission
  We report on candidate active galactic nuclei (AGN) discovered during the
monitoring of $\sim$500 bright (r < 18 mag) galaxies over several years with
the Kepler Mission. Most of the targets were sampled every 30 minutes nearly
continuously for a year or more. Variations of 0.001 mag and often less could
be detected reliably. About 4.0% (19) of our random sample continuously
fluctuated with amplitudes increasing with longer timescales, but the majority
are close to the limits of detectability with Kepler. We discuss our techniques
to mitigate the long term instrumental trends in Kepler light curves and our
resulting structure function curves. The amplitudes of variability over four
month periods, as seen in the structure functions and PSDs, can dramatically
change for many of these AGN candidates. Four of the candidates have features
in their Structure Functions that may indicate quasi-periodic behavior,
although other possibilities are discussed.
