X-ray spectral model from clumpy torus and its application to Circinus galaxy

We construct an X-ray spectral model for the clumpy torus in an active galactic nucleus (AGN), utilizing the Monte Carlo simulation for Astrophysics and Cosmology framework (MONACO: Odaka et al.2016). The geometry of the torus is the same as that in Nenkova et al. (2008), which assumes a power law distribution of clumps in the radial direction and a normal distribution in the elevation direction. We apply our model to the broadband X-ray spectrum of the Circinus galaxy observed with XMM-Newton, Suzaku, and NuSTAR. Our model can well reproduce the observed X-ray spectrum, yielding a hydrogen column density along the line-of-sight ${N_{\rm{H}}^{\rm{LOS}}} = 4.86_{ - 0.04}^{ + 0.07} \times {10^{24}}$ cm−2 and a torus angular width ${sigma = 14.7_{ - 0.39}^{ + 0.44}}$ degree.