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arXiv · 1807.02699

Probing AGN Inner Structure with X-ray Obscured Type 1 AGN

Teng Liu·Andrea Merloni·Jun-Xian Wang·Paolo Tozzi·Yue Shen·Marcella Brusa·Mara Salvato·Kirpal Nandra·Johan Comparat·Zhu Liu·Gabriele Ponti·Damien Coffey
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Abstract

Using the X-ray-selected active galactic nuclei (AGN) from the XMM-XXL north survey and the SDSS Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic follow-up of them, we compare the properties of X-ray unobscured and obscured broad-line AGN (BLAGN1 and BLAGN2; $N_\textrm{H}$below and above $10^{21.5}$ cm$^{-2}$), including their X-ray luminosity $L_X$, black hole mass, Eddington ratio $\lambda_{\textrm{Edd}}$, optical continuum and line features. We find that BLAGN2 have systematically larger broad line widths and hence apparently higher (lower) $M_{\textrm{BH}}$ ($\lambda_{\textrm{Edd}}$) than BLAGN1. We also find that the X-ray obscuration in BLAGN tends to coincide with optical dust extinction, which is optically thinner than that in narrow-line AGN (NLAGN) and likely partial-covering to the broad line region. All the results can be explained in the framework of a multi-component, clumpy torus model by interpreting BLAGN2 as an intermediate type between BLAGN1 and NLAGN in terms of an intermediate inclination angle.

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Teng Liu, Andrea Merloni, Jun-Xian Wang, Paolo Tozzi, Yue Shen, Marcella Brusa, Mara Salvato, Kirpal Nandra, Johan Comparat, Zhu Liu, Gabriele Ponti, Damien Coffey. 2018-07-07. Probing AGN Inner Structure with X-ray Obscured Type 1 AGN. https://doi.org/10.1093/mnras%2Fsty1751

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