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arXiv · 1611.09858

The Complete Infrared View of Active Galactic Nuclei from the 70-month Swift/BAT Catalog

Kohei Ichikawa·Claudio Ricci·Yoshihiro Ueda·Kenta Matsuoka·Yoshiki Toba·Taiki Kawamuro·Benny Trakhtenbrot·Michael J. Koss
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Abstract

We systematically investigate the near- (NIR) to far-infrared (FIR) photometric properties of a nearly complete sample of local active galactic nuclei (AGN) detected in the Swift/Burst Alert Telescope (BAT) all-sky ultra hard X-ray (14-195 keV) survey. Out of 606 non-blazar AGN in the Swift/BAT 70-month catalog at high galactic latitude of $|b|>10^{\circ}$, we obtain IR photometric data of 604 objects by cross-matching the AGN positions with catalogs from the WISE, AKARI, IRAS, and Herschel infrared observatories. We find a good correlation between the ultra-hard X-ray and mid-IR (MIR) luminosities over five orders of magnitude ($41 < \log (L_{14-195}/{\rm erg}~{\rm s}^{-1})< 46$). Informed by previous measures of the intrinsic spectral energy distribution of AGN, we find FIR pure-AGN candidates whose FIR emission is thought to be AGN-dominated with low starformation activity. We demonstrate that the dust covering factor decreases with the bolometric AGN luminosity, confirming the luminosity-dependent unified scheme. We also show that the completeness of the WISE color-color cut in selecting Swift/BAT AGN increases strongly with 14-195 keV luminosity.

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Kohei Ichikawa, Claudio Ricci, Yoshihiro Ueda, Kenta Matsuoka, Yoshiki Toba, Taiki Kawamuro, Benny Trakhtenbrot, Michael J. Koss. 2016-11-29. The Complete Infrared View of Active Galactic Nuclei from the 70-month Swift/BAT Catalog. https://doi.org/10.3847/1538-4357%2F835%2F1%2F74

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