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arXiv · 1712.01300

Where are Compton-thick radio galaxies? A hard X-ray view of three candidates

F. Ursini·L. Bassani·F. Panessa·A. Bazzano·A. J. Bird·A. Malizia·P. Ubertini
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Abstract

We present a broad-band X-ray spectral analysis of the radio-loud active galactic nuclei NGC 612, 4C 73.08 and 3C 452, exploiting archival data from NuSTAR, XMM-Newton, Swift and INTEGRAL. These Compton-thick candidates are the most absorbed sources among the hard X-ray selected radio galaxies studied in Panessa et al. (2016). We find an X-ray absorbing column density in every case below $1.5 \times 10^{24}$ cm$^{-2}$, and no evidence for a strong reflection continuum or iron K $α$ line. Therefore, none of these sources is properly Compton-thick. We review other Compton-thick radio galaxies reported in the literature, arguing that we currently lack strong evidences for heavily absorbed radio-loud AGNs.

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F. Ursini, L. Bassani, F. Panessa, A. Bazzano, A. J. Bird, A. Malizia, P. Ubertini. 2017-12-04. Where are Compton-thick radio galaxies? A hard X-ray view of three candidates. https://doi.org/10.1093/mnras%2Fstx3159

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