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arXiv · 1008.0722

Suzaku Observation of the Brightest Broad-Line Radio Galaxy 4C 50.55 (IGR J 21247+5058)

Fumie Tazaki·Yoshihiro Ueda·Yukiko Ishino·Satoshi Eguchi·Naoki Isobe·Yuichi Terashima·Richard F. Mushotzky
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Abstract

We report the results from a deep Suzaku observation of 4C 50.55 (IGR J 21247+5058), the brightest broad-line radio galaxy in the hard X-ray (> 10 keV) sky. The simultaneous broad band spectra over 1-60 keV can be represented by a cut-off power law with two layers of absorption and a significant reflection component from cold matter with a solid angle of Ω/2π\approx 0.2. A rapid flux rise by ~ 20% over 2 \times 10^4 sec is detected in the 2-10 keV band. The spectral energy distribution suggests that there is little contribution to the total X-ray emission from jets. Applying a thermal Comptonization model, we find that corona is optically thick (τ_e \approx 3) and has a relatively low temperature (kT_e \approx 30 keV). The narrow iron-K emission line is consistent with a picture where the standard disk is truncated and/or its inner part is covered by optically thick Comptonizing corona smearing out relativistic broad line features. The inferred disk structure may be a common feature of accretion flows onto black holes that produce powerful jets.

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Fumie Tazaki, Yoshihiro Ueda, Yukiko Ishino, Satoshi Eguchi, Naoki Isobe, Yuichi Terashima, Richard F. Mushotzky. 2010-08-04. Suzaku Observation of the Brightest Broad-Line Radio Galaxy 4C 50.55 (IGR J 21247+5058). https://doi.org/10.1088/0004-637x%2F721%2F2%2F1340

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