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The complex X-ray spectrum of NGC 4507

Giorgio Matt·Stefano Bianchi·Filippo D'Ammando·Andrea Martocchia
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Abstract

XMM-Newton and Chandra/HETG spectra of the Compton-thin (NH 4x10^{23} cm^{-2}) Seyfert 2 galaxy, NGC 4507, are analyzed and discussed. The main results are: a) the soft X-ray emission is rich in emission lines; an (at least) two--zone photoionization region is required to explain the large range of ionization states. b) The 6.4 keV iron line is likely emitted from Compton-thick matter, implying the presence of two circumnuclear cold regions, one Compton-thick (the emitter), one Compton-thin (the cold absorber). c) Evidence of an Fe xxv absorption line is found in the Chandra/HETG spectrum. The column density of the ionized absorber is estimated to be a few x10^{22} cm^{-2}.

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Giorgio Matt, Stefano Bianchi, Filippo D'Ammando, Andrea Martocchia. 2004-04-02. The complex X-ray spectrum of NGC 4507. https://doi.org/10.1051/0004-6361%3A20047045

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