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287 - A. J. Blustin 2009
We use a 380 ks XMM-Newton high-resolution RGS spectrum to look for narrow spectral features from the nuclear environment of 1H0707-495. We do not find any evidence of a line-of-sight ionized wind (warm absorber). We do, however, detect broad emissio n lines, of width ~5000 km s^-1, consistent with O VIII Ly-alpha, N VII Ly-alpha, C VI Ly-alpha and a Fe XIX/Fe XX/Ne IX He-alpha blend. Intriguingly, these lines have both blueshifted and redshifted components, whose velocity shifts are consistent with an origin in an accretion disc at ~1600 R_g from the black hole. The features can be interpreted as the narrow line cores of the disc reflection spectrum, thus providing independent support for the discline interpretation of the X-ray spectrum of 1H0707-495. We discuss the relevance of our findings for the `X-ray broad line region in other Seyferts, and for the origins of the optical broad line region itself.
The calculation of mass outflow rates of AGN winds is of great importance in understanding the role that such winds play in AGN-galaxy feedback processes. The mass outflow rates are, however, difficult to estimate since the volume filling factors of the winds are unknown. In this paper, we use constraints imposed by the observed radio emission to obtain upper limits to the volume filling factors of wind components in certain nearby AGN. We do this by predicting the 1.4 GHz radio flux densities emitted by those components, assuming a uniform wind, and then comparing these with the observed flux densities for each AGN at this frequency. We find that the upper limits to the volume filling factors are in the range 10^{-4}-0.5.
Broad absorption line quasars (commonly termed BALQSOs) contain the most dramatic examples of AGN-driven winds. The high absorbing columns in these winds, ~10^24 cm^-2, ensure that BALQSOs are generally X-ray faint. This high X-ray absorption means t hat almost all BALQSOs have been discovered through optical surveys, and so what little we know about their X-ray properties is derived from very bright optically-selected sources. A small number of X-ray selected BALQSOs (XBALQSOs) have, however, recently been found in deep X-ray survey fields. In this paper we investigate the X-ray and rest-frame UV properties of five XBALQSOs for which we have obtained XMM-Newton EPIC X-ray spectra and deep optical imaging and spectroscopy. We find that, although the XBALQSOs have an alpha_ox steeper by ~0.5 than normal QSOs, their median alpha_ox is nevertheless flatter by 0.30 than that of a comparable sample of optically selected BALQSOs (OBALQSOs). We rule out the possibility that the higher X-ray to optical flux ratio is due to intrinsic optical extinction. We find that the amount of X-ray and UV absorption due to the wind in XBALQSOs is similar, or perhaps greater than, the corresponding wind absorption in OBALQSOs, so the flatter alpha_ox cannot be a result of weaker wind absorption. We conclude that these XBALQSOs have intrinsically higher X-ray to optical flux ratios than the OBALQSO sample with which we compare them.
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