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arXiv · 1909.09762

Torus Constraints in ANEPD-CXO245: A Compton-thick AGN with Double-Peaked Narrow Lines

Abstract

We report on the torus constraints of the Compton-thick AGN with double-peaked optical narrow line region (NLR) emission lines, ANEPD-CXO245, at z=0.449 in the AKARI NEP Deep Field. The unique infrared data on this field, including those from the nine-band photometry over 2-24 $\mu$m with the AKARI Infrared Camera (IRC), and the X-ray spectrum from Chandra allow us to constrain torus parameters such as the torus optical depth, X-ray absorbing column, torus angular width ($\sigma$) and viewing angle ($i$). We analyze the X-ray spectrum as well as the UV-optical-infrared spectral energy distribution (UOI-SED) with clumpy torus models in X-ray (XCLUMPY; Tanimoto et al. 2019) and infrared (CLUMPY; Nenkova et al. 2008) respectively. From our current data, the constraints on $\sigma$--$i$ from both X-rays and UOI show that the line of sight crosses the torus as expected for a type 2 AGN. We obtain a small X-ray scattering fraction (<0.1%), which suggests narrow torus openings, giving preference to the bi-polar outflow picture of the double-peaked profile. Comparing the optical depth of the torus from the UOI-SED and the absorbing column density $N_{\rm H}$ from the X-ray spectrum, we find that the gas-to-dust ratio is $\gtrsim 4$ times larger than the Galactic value.

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Takamitsu Miyaji, Martín Herrera-Endoqui, Mirko Krumpe, Masaki Hanzawa, Ayano Shogaki, Shuji Matsuura, Atsushi Tanimoto, Yoshihiro Ueda, Tsuyoshi Ishigaki, Laia Barrufet, Hermann Brunner, Hideo Matsuhara, Tomotsugu Goto, Toshinobu Takagi, Chris Pearson, Denis Burgarella, Nagisa Oi, Matthew Malkan, Yoshiki Toba, Glenn J. White, Hitoshi Hanami. 2019-09-21. Torus Constraints in ANEPD-CXO245: A Compton-thick AGN with Double-Peaked Narrow Lines. https://doi.org/10.3847/2041-8213/ab46bc

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