XMM-Newton SAS Team releases version 7.0.0

The XMM-Newton SAS team is very pleased to announce the release of a new version of the SAS: SAS 7.0.0

The main changes in this version with respect to the former version, SAS 6.5.0, are:


  • upgraded EPIC MOS calibration, including column dependent CTI/Gain correction, improving line widths by upto ~15%
  • improved EPIC source detection and parameterisation tasks, especially related to the detection of extended sources. Robustness and efficiency have been increased, to make possible the 2XMM Catalogue derivation, which is in final preparation at the time of this release
  • inclusion of PSF correction for EPIC timing and burst modes in response matrix generation
  • support for arbitrary uniform binning of MOS and PN spectra


  • introduction of a time / spectral dependent RGS effective area correction, which in particular accounts for a decrease with time of the long-wavelength sensitivity. The cross calibration of RGS with the EPIC cameras has been considerably improved
  • flagging / discarding of RGS columns showing large Charge Transfer Inefficiency has been implemented, including the introduction of new calibration files in the system, improving small scale accuracy
  • background modelling can be performed now for the new recommmended (and taken by default) regions selection areas. This requires the use of restructured calibration files, that accomodate template backgrounds for different selection criteria


  • the OM image chain (omichain) can now process full frame high resolution data, which failed before because of inconsistent header keywords
  • the structure of the output source lists has been changed, mainly in the final combined list produced by omsrclistcomb
  • fast mode: the time dependent sensitivity degradation correction, implemented for image mode in SAS 6.5.0 is now also available in fast mode
  • OM grism data processing: a series of small changes mainly related to improvements in the identification and extraction of the spectra and the interpretability of the data. To be consistent with these changes, it has been necessary to modify the flux calibration of the UV grism. Users of SAS 7.0.0 grism data reduction must use the new OM_GRISMCAL_0004.CCF. For the first time, the grism processing chain includes the astrometry task omatt so that the sources of all extracted spectra (multiobject spectroscopy) are assigned astronomical coordinates. Users should be aware that this facility is still in a preliminary state, and therefore the obtained coordinates may still have large errors (up to one arcmin). Note that grism astrometry requires OM_ASTROMET_0012.CCF

In addition to the above several minor bug fixes have been implemented.


Please note that the new calibration constituent files (CCF) are needed for the improvement achieved by the EPIC MOS CTI correction as well as by the RGS "cool" pixels determination and temporally-dependent effective area calculation.

The list of new CCFs follows:

  • EMOS[1-2]_CTI_00[30-42].CCF containing the column dependent CTI correction factors for 13 different epochs. Please note that at the time of the SAS 7.0.0 release the calibration files are still in preparation. They will be released 3-4 weeks later. In the meantime, using the current CCF elements, SAS 7.0.0 will calculate the CTI without the column-dependent correction, as for SAS 6.5.0
  • RGS[1-2]_COOLPIX_0001.CCF contain the lists of large CTI columns, which can be discarded by applying the new rgsbadpix (and rgsproc) parameter keepcool=no
  • RGS[1-2]_EFFAREACORR_0003.CCF with the effective area values of 5 different epochs, used for interpolation
  • RGS[1-2]_TEMPLATEBCKGND_0003.CCF containing the different template backgrounds for different selection criteria.
  • OM_GRISMCAL_0004.CCF, which has to be used by the grism data processing as implemented in SAS 7.0.0

For further details on obtaining SAS 7.0.0 please visit our SAS Pages