Enhanced XMM-Newton Spectral-fit Database

3XMM spectral-fit database (XMMFITCAT)


  1. Catalogue overview
  2. Access to the spectral-fit database
  3. Access to the spectral data

Catalogue overview

The XMM-Newton spectral-fit catalogue (XMMFITCAT) contains spectral-fitting results for 146,825 detections, corresponding to 99,356 unique sources. This catalogue is produced by applying automated spectral fits to the EPIC spectral data contained within the XMM-Newton serendipitous source catalogue. The version of the catalogue used to construct the current XMMFITCAT is 3XMM-DR6.

3XMM-DR6 is the third generation catalogue of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory, and has been created by the XMM-Newton Survey Science Centre (SSC) on behalf of ESA. The 3XMM-DR6 catalogue contains photometric information for 678,680 source detections,corresponding to 468,440 unique sources. As part of the catalogue production, spectra and time series are extracted in the case o detections with more than 100 counts collected in the EPIC camera. This corresponds to 149,968 detections, and 102,157 unique sources.

The XMM-Newton spectral-fit database is constructed by using spectral data from the 3XMM-DR6 catalogue, but not all detections with extracted spectra are included in this database. To ensure the reliability of the spectral-fitting results, several constrains have been imposed to the number of counts collected in the X-ray spectra and as result, some detections are rejected in the automated spectral-fit pipeline (see Catalogue description for details).

Access to the spectral-fit database

The spectral-fit database consists of a FITS table with one row for each source detection, and 214 columns containning information about the observation, and spectral-fitting results for each spectral model applied (best-fit parameters and errors, fluxes, and goodness of fit). The table can be downloaded from the following link:

XMMFITCAT can also be queried by using LEDAS, the astronomical database service and access to archive data at the University of Leicester. The spectral-fitting results can also be accessed by using XCAT-DB, a Web-based tool maintained by the Observatoire Astronomique de Strasbourg. The list of 3XMM-DR6 spectra used in the spectral fits for each detection can be downloaded from the following link:

Access to the spectral data

In the construction of this spectral-fit database, the spectral data used were the pipe-line extracted source and background spectra, and ancillary matrices provided by the XMM-Newton SSC in the 3XMM-DR6 catalogue. Response matrices were the canned matrices provided by the XMM-Newton SOC. The database does not contain spectral data but spectral-fitting results. The spectral data used in the construction of this database can be retrieved by using any of the Web-based user interfaces listed below. Spectral data for a given source detection can be identified by using the value of the DETID column within the 3XMM-DR6 catalogue and this spectral-fit database.