XMM-Newton spectral-fit database

XMM-SDSS sample


In order to test the applicability of this project to a scientific case, the automated fitting process has been applied to a large and well-defined sample of X-ray sources extracted from the XMM-Newton/SDSS-DR7 (Sloan Digital Sky Survey, Data Release 7) cross-correlation presented in Georgakakis & Nandra (2011). The full sample contains more than 40000 X-ray sources. The X-ray sample used here is composed of the sources detected in the hard band (2-8 keV), ∼14000 sources. This hard sample is divided in three sub-samples:

  1. Spectroscopic sample, composed of sources with spectroscopic redshifts: 1275 X-ray sources.
  2. Photometric sample, composed of sources with only photometric redshifts: 7477 X-ray sources
  3. And sources not detected in the optical (SDDS-DR7): 5305 X-ray sources.

For the spectroscopic sample, there are spectral data available within the 3XMM-Newton catalogue for ∼80% (1018 sources out of 1275) of the sources, and for the photometric sample for ∼60% (4288 sources out of 7477), since this later sample is composed of fainter sources on average. There are spectral available for only ∼34% of the X-ray sources with no optical counterpart, being this sample composed of the faintest sources.


The XMM-SDSS test catalog

The automated spectral fitting results for all the XMM/SDSS hard sub-samples can be accessed in FITS format via the following links:

Sub-sample Spectral-fit catalogues README file
Spectroscopic redshifts xmmsdss_hard_specz_fitcatalog.fits.tar.gz README_hard_specz.txt
Photometric redshifts xmmsdss_hard_photz_fitcatalog.fits.tar.gz README_hard_photz.txt
No optical counterpart xmmsdss_hard_noopt_fitcatalog.fits.tar.gz README_hard_noopt.txt

Users are strongly recommended to read carefully the README_sample.txt files before using any of the information contained in the catalogues. Note also that the models applied to the X-ray sources with either spectroscopic or photometric redshifts include the effect of redshift, whereas the models applied to the X-ray sources with no optical counterpart are the same as the ones that are applied to the full 3XMM-DR6 catalogue, i.e., they do not make use of any redshift information. The models for the sources with either spectroscopic or photometric redshifts include an additional absorption component whose column density is fixed to the Galactic value at the sources coordinates.