| Dr James Reeves (University of Leicester) |
| 6th February 2002 |
| XMM-Newton Results on Active Galactic Nuclei |
| Observations of various type I AGN, obtained during the PV-CAL and GTO and AO-1 phases of XMM-Newton are presented. Here I review the properties of the iron K emission lines observed by XMM-Newton. In contrast to earlier ASCA observations, we find that the majority of objects show narrow iron K lines from cold neutral matter that must originate from material more distant than the accretion disc, perhaps the putative molecular torus. The strength of the narrow line decreases with luminosity, implying a reduction in the solid angle of the obscuring material in luminous quasars - this may have implications for the occurance of type II quasars. There are only a few examples of the broad iron K line, in one case (MCG -6-30-15) the extreme breadth requires a Kerr metric for the central black hole. In higher luminosity sources, the broad lines can be ionised, suggesting disc photoionisation plays an important role in the emergent spectrum. I will also discuss new features discovered in the X-ray spectra of AGN, including two quasars (PDS 456 and PG 1211+143) where deep iron K-shell absorption edges are observed. The RGS spectra of these sources exhibit high ionisation absorption lines, suggesting that a high column density of ionised matter lies along the line of sight. |
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