Enhanced XMM-Newton Spectral-fit Database

3XMM spectral-fit Z database (XMMFITCAT-Z)


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

Catalogue overview

The XMM-Newton spectral-fit Z catalogue (XMMFITCAT-Z) contains spectral-fitting results for CATD detections, corresponding to CATS unique sources. This catalogue is produced by applying automated spectral fits to the EPIC spectral data contained within the XMM-Newton serendipitous source catalogue and using the distance information contained in XMMPZCAT. The version of the catalogue used to construct the current XMMFITCAT is CATV.

CATV 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 CATV catalogue contains photometric information for CATD source detections, corresponding to CATS unique sources. As part of the catalogue production, spectra and time series are extracted in the case of detections with more than 100 counts collected in the EPIC camera. This corresponds to CATD detections, and CATS unique sources.

XMMPZCAT contains 100,178 3XMM sources outside the Galactic plane (|b|>20 deg) with highly reliable optical counterparts in the SDSS-DR13 or Pan-STARRS-DR1 catalogues. It offers photo-z for about 50% of the X-ray sources within the XMM-Newton observations selected for building the catalogue.

The XMM-Newton spectral-fit database is constructed by using spectral data from the CATV catalogue, but not all detections with extracted spectra are included in this database. To ensure the reliability of the spectral-fitting results, a constrain has 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. Moreover, only detections with redshifts in XMMPZCAT have been included (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 157 columns containing information about the observation, and spectral-fitting results for each spectral model applied (best-fit parameters and errors, fluxes, luminosities, and goodness of fit). The table can be downloaded from the following link:

We also offer an easy-to-use browser for XMMFITCAT-Z. It allows very simple queries based on DETID, SRCID, OBS_ID and IAUNAME. The browser can be used for quick access and visualization of best fit models, fluxes, luminosities and spectral plots. In addition, a file with the full database in sqlite format can be downloaded. This file contains significantly more information than the FITS version above (e.g. the CATV spectra used in the spectral fits) and allows the user to do advanced queries using SQL language. Check the README file for a full description of the database schema.

Here we also provide the sample of 977 X-ray absorbed AGN identified from the XMMFITCAT-Z catalogue, as presented in Ruiz et al. 2020.

Access to the spectral data

In the construction of this spectral-fit database, we used the pipe-line extracted source and background spectra, and ancillary matrices provided by the XMM-Newton SSC in the CATV 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 CATV catalogue or XMMFITCAT-Z.