Neutral Ionized Absorbers or Reflection Dominated Models

The measured edge energy and the sharpness of the edge as observed in the two objects are comparable to the energy resolution of the EPIC instruments (about 200 eV). In Fig. 22.7 is shown that in the second observation of 1H 0707-495 the energy of the sharp spectral drop has been significantly shifted to 7.5 keV. For IRAS 13224-3809 the edge energy is even higher, at 8.2 keV, corresponding to Fe IXX to Fe XXIII and a width of the feature of about 600 eV, in contrast to the observations. In addition, ionized Fe would result in a K^ UTA feature ([39,40]) which remains undetected in the XMM-Newton observations. Therefore, if absorption is the underlying physical process, we observe neutral Fe with significant outflow velocities of about 0.05 c (1H 0707-495; second observation) and 0.15 c for IRAS 13224-3809.

An alternative explanation is a reflection dominated model, where the sharp spectral drop is due to the blue horn of a strong relativistically broadened Fe K line [16]. The missing Fe Kfí UTA feature and the sharpness point to an absorption

Energy (keV)

Fig. 22.7 Left: XMM-Newton spectra of 1H 0707-495 taken in October 2000 (low flux state) and in October 2002 (high flux state). The sharp spectral drop has been shifted from 7.1 keV to 7.5 keV. The sharpness of the feature suggests absorption by neutral Fe with outflow velocities of about 0.05 c. Right: XMM-Newton spectrum of IRAS 13224-3809. The sharp spectral drop is shifted to even higher energies of 8.2 keV, suggesting outflowing velocities of 0.15 c

Energy (keV)

Energy (keV)

Fig. 22.7 Left: XMM-Newton spectra of 1H 0707-495 taken in October 2000 (low flux state) and in October 2002 (high flux state). The sharp spectral drop has been shifted from 7.1 keV to 7.5 keV. The sharpness of the feature suggests absorption by neutral Fe with outflow velocities of about 0.05 c. Right: XMM-Newton spectrum of IRAS 13224-3809. The sharp spectral drop is shifted to even higher energies of 8.2 keV, suggesting outflowing velocities of 0.15 c

process causing the sharp spectral drops in NLSls. Finally we note that the spectrum consisting of a dominant soft X-ray component and a hard tail is strikingly similar to the spectra of the black-hole binaries at high luminosities [50]. This strongly suggests that the AGN shown in Fig. 22.6 and Fig. 22.7 are analogues of the soft-state black-hole binaries.

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