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New {\it Chandra} Results on Seyfert I galaxies: Fe-K lines

U. Padmanabhan·T. Yaqoob
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Abstract

We present measurements of the Fe-K line for nine Seyfert I galaxies using Chandra High Energy Transmission Grating Spectrometer (HETGS) data. The centroid energies are narrowly dispersed (6.403 +/- 0.062 keV) and indicate an origin of the line cores in cold matter. If {\it all} the lines in this sample were the peaks of a relativistically broadened disk line, it would require unrealistically fine tuning. However, at least three of the nine AGN clearly show a complex Fe-K line with an underlying broad component, possibly from a disk. In the others, an apparently narrow Fe-K line (even if it is resolved by Chandra) may still be due to the peak of a disk line. To distinguish this scenario from an origin in distant matter requires variability information.

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U. Padmanabhan, T. Yaqoob. 2002-11-17. New {\it Chandra} Results on Seyfert I galaxies: Fe-K lines. https://arxiv.org/abs/astro-ph/0211386

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