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arXiv · 2210.11506

Compton-thick AGN in the NuSTAR Era. IX. A Joint NuSTAR and XMM-Newton Analysis of Four Local AGN

Ross Silver·Nuria Torres-Alba·Xiurui Zhao·Stefano Marchesi·Andrealuna Pizzetti·Isaiah Cox·Marco Ajello·Giancarlo Cusumano·Valentina La Parola·Alberto Segreto
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Abstract

We present the results of the broadband X-ray spectral analysis of simultaneous NuSTAR and XMM-Newton observations of four nearby Compton-thick active galactic nuclei (AGN) candidates selected from the Swift-Burst Alert Telescope (BAT) 150-month catalog. This work is part of a larger effort to identify and characterize all Compton-thick (NH >= 10^24 cm^-2) AGN in the local Universe (z < 0.05). We used three physically motivated models -- MYTorus, borus02, and UXClumpy -- to fit and characterize these sources. Of the four candidates analyzed, 2MASX J02051994-0233055 was found to be an unobscured (NH < 10^22 cm^-2) AGN, 2MASX J04075215-6116126 and IC 2227 to be Compton-thin (10^22 cm^-2 < NH < 10^24 cm^-2) AGN, and one, ESO 362-8, was confirmed to be a Compton-thick AGN. Additionally, every source was found to have a statistically significant difference between their line-of-sight and average torus hydrogen column density, further supporting the idea that the obscuring material in AGN is inhomogeneous. Furthermore, half of the sources in our sample (2MASX J02051994-0233055 and 2MASX J04075215-6116126) exhibited significant luminosity variation in the last decade, suggesting that this might be a common feature of AGN.

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Ross Silver, Nuria Torres-Alba, Xiurui Zhao, Stefano Marchesi, Andrealuna Pizzetti, Isaiah Cox, Marco Ajello, Giancarlo Cusumano, Valentina La Parola, Alberto Segreto. 2022-10-20. Compton-thick AGN in the NuSTAR Era. IX. A Joint NuSTAR and XMM-Newton Analysis of Four Local AGN. https://doi.org/10.3847/1538-4357%2Fac9bf8

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