NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-21 T07:35:12 PDT
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For refcode 2008ApJ...674..686W:
Retrieve 23 NED objects in this reference.
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2008ApJ...674..686W X-Ray Properties of an Unbiased Hard X-Ray-detected Sample of Active Galactic Nuclei Winter, Lisa M.; Mushotzky, Richard F.; Tueller, Jack; Markwardt, Craig Abstract. The Swift {gamma}-ray observatory's Burst Alert Telescope (BAT) has detected a sample of AGNs based solely on their hard X-ray flux (14-195 keV). In this paper we present for the first time XMM-Newton X-ray spectra for 22 BAT AGNs with no previously analyzed X-ray spectra. If our sources are a representative sample of the BAT AGNs, as we claim, our results present for the first time global X-ray properties of an unbiased toward absorption (n_H_<3x10^25^ cm^-2^), local (=0.03), AGN sample. We find 9/22 low-absorption (n_H_<10^23^ cm^-2^), simple power-law model sources, where 4 of these sources have a statistically significant soft component. Among these sources, we find the presence of a warm absorber statistically significant for only one Seyfert 1 source, contrasting with the ASCA results of Reynolds and George and coworkers, who find signatures of warm absorption in half or more of their Seyfert 1 samples at similar redshifts. In addition, the remaining sources (13/22) have more complex spectra, well fitted by an absorbed power law at E>2.0 keV. Five of the complex sources are classified as Compton-thick candidates. Further, we find four more sources with properties consistent with the hidden/buried AGNs reported by Ueda and coworkers. Finally, we include a comparison of the XMM-Newton EPIC spectra with available Swift X-Ray Telescope (XRT) observations. From these comparisons, we find 6/16 sources with varying column densities, 6/16 sources with varying power-law indices, and 13/16 sources with varying fluxes, over periods of hours to months. Flux and power-law index are correlated for objects where both parameters vary. Key words: Galaxies: Active, Surveys, X-Rays: Galaxies
Retrieve 23 NED objects in this reference.
Please click here for ADS abstract

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