AGNSDSSXMM - SDSS/XMM-Newton AGN Spectral Properties Catalog
This table contains the subset of 153 brighter hard X-ray sources in the XMM-Newton/Sloan Digital Sky Survey (SDSS) sample which have 2-8 keV fluxes > 3 x 10-14 erg cm-2 s-1, excluding a number of sources with extended optical morphology and blue colors, as well as 4 sources with X-ray to optical fluxes < 0.1 which are fit better with stellar rather than QSO templates.
Much more information on the SDSS is available at the project's web site at http://www.sdss.org/.
XMM-Newton and Chandra measurements of the AGN intrinsic absorption: dependence on luminosity and redshift. Akylas A., Georgantopoulos I., Georgakakis A., Kitsionas S., Hatziminaoglou E. <Astron. Astrophys., 459, 693-701 (2006)> =2006A&A...459..693A
A running X-ray source number in order of increasing J2000.0 Right Ascension.
The preferred designation for the X-ray source using the '[AGG2006]' prefix (for Akylas, Georgantopoulos, Georgakakis, 2006) and the source number, as recommended by the CDS Dictionary of Nomenclature of Celestial Objects.
The Right Ascension of the X-ray source in the selected equinox. This was given in J2000.0 coordinates in decimal degrees to a precision of 0.001 degrees (3.6") in the original table.
The Declination of the X-ray source in the selected equinox. This was given in J2000.0 coordinates in decimal degrees to a precision of 0.001 degrees (3.6") in the original table.
The Galactic Longitude of the X-ray source.
The Galactic Latitude of the X-ray source.
The X-ray power-law photon index, Gamma. For sources with adequate count statistics (net source counts >100), the authors used the Chi-squared statistic technique. The data were grouped to give a minimum of 15 counts per bin to ensure that Gaussian statistics apply. The authors adopted an absorbed power-law model and attempted to constrain the intrinsic absorption column density NH (i.e., having subtracted the Galactic absorption) and Gamma. For the sources with limited photon statistics (net counts <100), they used the C-statistic technique specifically developed to extract spectral information from data with a low signal-to-noise ratio. In this case, the data were grouped to give a minimum of 1 count per bin to avoid zero count bins. The authors tried to constrain the intrinsic column densities using an absorbed power-law model with Gamma fixed to 1.8. In both cases, the spectral fittings were performed in the 0.3 - 8 keV energy band where the sensitivity of the XMM-Newton detectors is the highest.
The positive error in the power-law photon index, Gamma.
The negative error in the power-law photon index, Gamma.
The upper or lower limit to the observed best-fit absorption column density, NH.
The observed best-fit value of the Hydrogen column density, NH, in atoms cm-2.
The positive error in the observed best-fit value of the Hydrogen column density, NH, in atoms cm-2.
The negative error in the observed best-fit value of the Hydrogen column density, NH, in atoms cm-2.
The intrinsic 2 - 8 keV flux of the X-ray source, in erg cm-2 s-1.
The redshift (either spectroscopic or photometric according to the value of the opt_ctrprt_flag parameter) of the SDSS counterpart to the X-ray source.
The Galactic column density in the direction of the observed field, (NH)Gal, in atoms cm-2.
The intrinsic rest-frame column density, (NH)Int, in atoms cm-2.
The logarithm of the intrinsic 2 - 8 keV luminosity of the source, in erg s-1.
This parameter flags the status of the optical counterpart to the X-ray source:
1 = spectroscopic optical counterpart 2 = photometric optical counterpart 3 = absence of an optical counterpart