AAS 205th Meeting, 9-13 January 2005
Session 27 Active Galactic Nuclei
Poster, Monday, January 10, 2005, 9:20am-6:30pm, Exhibit Hall

## [27.14] Relativistic Emission Lines in AGN Spectra

P. M. Ogle (JPL/NRC)

I review the evidence for relativistic emission lines in the X-ray spectra of active galactic nuclei observed with XMM-Newton. It is postulated that these lines originate in the inner accretion flow within several gravitational radii of a supermassive black hole. If so, they provide invaluable clues about the geometry and ionization of the region where most of the gravitational energy is liberated. They can also be used to probe the properties of spacetime near black holes and to estimate a lower limit on the spin of the black hole.

I classify the broad-band X-ray spectra of AGN with the best candidate relativistic Fe K\alpha and O VIII Ly\alpha lines. These sources appear to be reflection dominated, with broad features from highly ionized iron and oxygen. I use such features to identify a larger sample of reflection-dominated objects culled from the XMM-Newton Archive. These are prime targets to be observed with longer exposure times to measure the detailed Fe K\alpha and O VIII Ly\alpha emission line profiles. With a larger sample at hand, it will be possible to study the effects of accretion rate, black hole mass, black hole spin, inclination, and radio-loudness on the X-ray spectra and spectral energy distributions of AGN.

This work is supported by the National Research Council.