Several X-ray spectral models for tori in active galactic nuclei (AGNs) are available to constrain the properties of tori; however, the accuracy of these models has not been verified. We recently construct a code for the torus using Geant4, which can easily handle different geometries (Liu & Li 2014). Thus, we adopt the same assumptions as Murphy & Yaqoob (2009, hereafter MY09) and Brightman & Nandra (2011, hereafter BN11) and try to reproduce their spectra. As a result, we can reproduce well the reflection spectra and the strength of the Fe Kα line of MY09, for both \NH=1024 and 1025 cm−2. However, we cannot produce the strong reflection component of BN11 in the low-energy band. The origin of this component is the reflection from the visible inner wall of the torus, and it should be very weak in the edge-on directions under the geometry of BN11. Therefore, the behaviour of the reflection spectra in BN11 is not consistent with their geometry. The strength of the Fe Kα line of BN11 is also different from our results and the analytical result in the optically thin case. The limitation of the spectral model will bias the parameters from X-ray spectral fitting.
@article{arxiv.1501.00557,
title = {A direct comparison of X-ray spectral models for tori in active galactic nuclei},
author = {Yuan Liu and Xiaobo Li},
journal= {arXiv preprint arXiv:1501.00557},
year = {2015}
}