Sloan Digital Sky Survey (DR5)/XMM-Newton Quasar Survey Catalog

The authors fit a single power law, a fixed power law with intrinsic absorption left free to vary, and an absorbed power-law model to all quasars with X-ray signal-to-noise ratio >= 6, resulting in a weighted mean photon index Gamma = 1.91 +/- 0.08, with an intrinsic dispersion sigma(Gamma) = 0.38. For the 55 sources (11.6%) that prefer intrinsic absorption, the authors find a weighted mean N<sub>H</sub> = 1.5 +/- 0.3 x 10<sup>21</sup> cm<sup>-2</sup>.

They find that Gamma correlates significantly with optical color, Delta(g-i), the optical-to-X-ray spectral index (alpha<sub>ox</sub>), and the X-ray luminosity. While the first two correlations can be explained as artifacts of undetected intrinsic absorption, the correlation between Gamma and X-ray luminosity appears to be a real physical correlation, indicating a pivot in the X-ray slope. This table was created by the HEASARC in July 2009 based on electronic versions of Tables 1 and 2 from the paper which were obtained from the Astrophysical Journal web site.

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