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Sloan Digital Sky Survey/XMM-Newton AGN Spectral Properties Catalog

Metadata Updated: September 19, 2025

Bright XMM-Newton data are combined with the Chandra Deep Field South observations to explore the behavior of the intrinsic AGN absorption, as a function of redshift and luminosity. The sample consists of 359 sources selected in the hard 2 - 8 keV band, spanning the flux range from 6 x 10<sup>-16</sup> - 3 x 10<sup>-13</sup> erg/cm<sup>2</sup>/s with a high rate of spectroscopic or photometric redshift completeness (100 and 85 percent for the Chandra and XMM-Newton data, respectively). The authors derive the column density values using X-ray spectral fits. They find that the fraction of obscured AGN falls with increasing luminosity in agreement with previous findings. The fraction of obscured AGN shows an apparent increase at high redshifts (z > 2). Simulations show that this effect can most probably be attributed to the fact that at high redshifts the column densities are overestimated. 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<sup>-14</sup> erg cm<sup>-2</sup> s<sup>-1</sup>, 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 <a href="http://www.sdss.org/">http://www.sdss.org/</a>;. This table was created by the HEASARC in July 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/459/693">CDS Catalog J/A+A/459/693</a> file table2.dat. This is a service provided by NASA HEASARC .

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/agnsdssxmm
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id b44a3e70-d932-40a8-974f-7cbc65d0324e
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/agnsdssxmm.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 1ff1bfa7efe891d97b4c5e4325adb7d03572ff67a1cece695ec85bc043689388
Source Schema Version 1.1

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