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arXiv · 1701.03938

X-ray spectral properties of seven heavily obscured Seyfert 2 galaxies

Stefano Marchesi·Marco Ajello·Andrea Comastri·Giancarlo Cusumano·Valentina La Parola·Alberto Segreto
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Abstract

We present the combined Chandra and Swift-BAT spectral analysis of seven Seyfert 2 galaxies selected from the Swift-BAT 100-month catalog. We selected nearby (z<=0.03) sources lacking of a ROSAT counterpart and never previously observed with Chandra in the 0.3-10 keV energy range, and targeted these objects with 10 ks Chandra ACIS-S observations. The X-ray spectral fitting over the 0.3-150 keV energy range allows us to determine that all the objects are significantly obscured, having NH>=1E23 cm^(-2) at a >99% confidence level. Moreover, one to three sources are candidate Compton thick Active Galactic Nuclei (CT-AGN), i.e., have NH>=1E24 cm^(-2). We also test the recent "spectral curvature" method developed by Koss et al. (2016) to find candidate CT-AGN, finding a good agreement between our results and their predictions. Since the selection criteria we adopted have been effective in detecting highly obscured AGN, further observations of these and other Seyfert 2 galaxies selected from the Swift-BAT 100-month catalog will allow us to create a statistically significant sample of highly obscured AGN, therefore better understanding the physics of the obscuration processes.

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Stefano Marchesi, Marco Ajello, Andrea Comastri, Giancarlo Cusumano, Valentina La Parola, Alberto Segreto. 2017-01-14. X-ray spectral properties of seven heavily obscured Seyfert 2 galaxies. https://doi.org/10.3847/1538-4357%2F836%2F1%2F116

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