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MYTorus fit to NGC 4945 Suzaku data

MYTorus fit to NGC 4945 Suzaku data: unfolded photon spectra
MYTorus fit to NGC 4945 Suzaku data: Fe K alpha line region

MYTorus fits to Suzaku data for the Seyfert 2 galaxy NGC 4945 show that the line-of-sight column density is $\sim 2-6 \times 10^{24} \ {\rm cm^{-2}}$ (depending on details of the applied model), and that the global average column density is consistent with the line-of-sight column density. Many previous stuides deduced that the obscuring structure in this Compton-thick AGN must be ring-like, observed edge-on. However, such a model was never actually tested.

Our analysis showed that the prevailing picture model fails to explain the data, which instead demand a reflection and fluorescence spectrum observed through “holes” in a clumpy Compton-thick medium. We calculated new intrinsic luminosities for our solutions and they were lower than those deduced from disk-reflection models. See Yaqoob (2012) for full details.

The Compton-thick scattered continuum component can be seen in blue (labeled CS) in panel (a). Standard disk-reflection models simply assumed the column density to be infinite. The line-of-sight, direct (unscattered, or zeroth-order) contininuum component is shown in orange in panel (a), and labeled as “Z.” Note that the Fe K$\alpha$ and Fe K$\beta$ emission lines are self-consistently calculated and give an excellent fit to the data.

Note that the Fe XXV He-like emission line is not part of the MYTorus model and is included as a separate component as it must have a different origin to the neutral Fe K$\alpha$ line.

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