The high energy emission line spectrum of NGC 1068

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 Kα Compton shoulder implies that the neutral reflector is Compton-thick, likely the visible inner wall of the NH > 1025 cm-2 absorber. From the equivalent width of the ionized iron lines a column density of a few ×1021 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.