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The high energy emission line spectrum of NGC 1068

Giorgio Matt·Stefano Bianchi·Matteo Guainazzi·Silvano Molendi
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Abstract

We present and discuss the high energy (E>4 keV) XMM-Newton spectrum of the Seyfert 2 galaxy, NGC 1068. Possible evidence for flux variability in both the neutral and ionized reflectors with respect to a BeppoSAX observation taken 3.5 years before is found. Several Fe and Ni emission lines, from both neutral and highly ionized material, are detected. The intensity of the iron K$α$ Compton shoulder implies that the neutral reflector is Compton--thick, likely the visible inner wall of the $N_H > 10^{25}$ cm$^{-2}$ absorber. From the equivalent width of the ionized iron lines a column density of a few $\times 10^{21}$ cm$^{-2}$ is deduced for the hot ionized reflector. Finally, an iron (nickel) overabundance, when compared to solar values, of about 2 (4) with respect to lower Z elements, is found.

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Giorgio Matt, Stefano Bianchi, Matteo Guainazzi, Silvano Molendi. 2003-10-17. The high energy emission line spectrum of NGC 1068. https://doi.org/10.1051/0004-6361%3A20031635

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