The Suzaku View of the Swift/BAT AGNs (II): Time Variability and Spectra
  of Five "Hidden" AGNs
  The fraction of Compton thick sources is one of the main uncertainties left
in understanding the AGN population. The Swift Burst Alert Telescope (BAT)
all-sky survey, for the first time gives us an unbiased sample of AGN for all
but the most heavily absorbed sources (log NH > 25). Still, the BAT spectra (14
- 195 keV) are time-averaged over months of observations and therefore hard to
compare with softer spectra from the Swift XRT or other missions. This makes it
difficult to distinguish between Compton-thin and Compton-thick models. With
Suzaku, we have obtained simultaneous hard (> 15 keV) and soft (0.3 - 10 keV)
X-ray spectra for 5 Compton-thick candidate sources. We report on the spectra
and a comparison with the BAT and earlier XMM observations. Based on both flux
variability and spectral shape, we conclude that these hidden sources are not
Compton-thick. We also report on a possible correlation between excess variance
and Swift BAT luminosity from the 16 d binned light curves, which holds true
for a sample of both absorbed (4 sources), unabsorbed (8 sources), and Compton
thick (Circinus) AGN, but is weak in the 64 day binned BAT light curves.
