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arXiv · 1911.05820

The Broadband X-ray Spectrum of the X-ray Obscured Type 1 AGN 2MASX J193013.80+341049.5

Nikita Kamraj·Mislav Baloković·Murray Brightman·Daniel Stern·Fiona A. Harrison·Roberto J. Assef·Michael J. Koss·Kyuseok Oh·Dominic J. Walton
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Abstract

We present results from modeling the broadband X-ray spectrum of the Type 1 AGN 2MASX J193013.80+341049.5 using NuSTAR, Swift and archival XMM-Newton observations. We find this source to be highly X-ray obscured, with column densities exceeding 10$^{23}$ cm$^{-2}$ across all epochs of X-ray observations, spanning an 8 year period. However, the source exhibits prominent broad optical emission lines, consistent with an unobscured Type 1 AGN classification. We fit the X-ray spectra with both phenomenological reflection models and physically-motivated torus models to model the X-ray absorption. We examine the spectral energy distribution of this source and investigate some possible scenarios to explain the mismatch between X-ray and optical classifications. We compare the ratio of reddening to X-ray absorbing column density ($E_{B-V}/N_{H}$) and find that 2MASX J193013.80+341049.5 likely has a much lower dust-to-gas ratio relative to the Galactic ISM, suggesting that the Broad Line Region (BLR) itself could provide the source of extra X-ray obscuration, being composed of low-ionization, dust-free gas.

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Nikita Kamraj, Mislav Baloković, Murray Brightman, Daniel Stern, Fiona A. Harrison, Roberto J. Assef, Michael J. Koss, Kyuseok Oh, Dominic J. Walton. 2019-11-13. The Broadband X-ray Spectrum of the X-ray Obscured Type 1 AGN 2MASX J193013.80+341049.5. https://doi.org/10.3847/1538-4357%2Fab57fc

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