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arXiv · 0903.2802

The Suzaku View of the Swift/BAT AGNs (II): Time Variability and Spectra of Five "Hidden" AGNs

Lisa Winter·Richard Mushotzky·Yuichi Terashima·Yoshihiro Ueda
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Abstract

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.

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Lisa Winter, Richard Mushotzky, Yuichi Terashima, Yoshihiro Ueda. 2009-03-16. The Suzaku View of the Swift/BAT AGNs (II): Time Variability and Spectra of Five "Hidden" AGNs. https://doi.org/10.1088/0004-637x/701/2/1644

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