X‐ray reflection in the nearby Seyfert 2 galaxy NGC 1068

Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH
Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.52). 05/2006; 368(2):707 - 714. DOI: 10.1111/j.1365-2966.2006.10139.x
Source: arXiv

ABSTRACT We use the full broad-band XMM–Newton European Photon Imaging Camera (EPIC) data to examine the X-ray spectrum of the nearby Seyfert 2 galaxy NGC 1068, previously shown to be complex with the X-ray continuum being a sum of components reflected/scattered from cold (neutral) and warm (ionized) matter, together with associated emission-line spectra. We quantify the neutral and ionized reflectors in terms of the luminosity of the hidden nucleus. Both are relatively weak, a result we interpret on the unified Seyfert model by a near side-on view to the putative torus, reducing the visibility of the illuminated inner surface of the torus (the cold reflector), and part of the ionized outflow. A high inclination in NGC 1068 also provides a natural explanation for the large (Compton-thick) absorbing column in the line-of-sight to the nucleus. The emission line fluxes are consistent with the strength of the neutral and ionized continuum components, supporting the robustness of the spectral model.

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