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SEQ Processing

 

Finally, the SEQ S/W package generates the output of the scientific data set. OBIs, which belong together, will be merged into a single data sequence to produce a general observation master data set (OMAS). Accordingly, this data set is used to perform a preliminary scientific analysis taking into account the corresponding detector properties of the PSPC and HRI, respectively.

PSPC processing

uses different sliding-window detection algorithms with several detection cell sizes to locate sources in three energy bands (broad, soft, and hard), and correlates and merges these into a single source candidate list. This source list is then compared with the result of a second source detection method (maximum likelihood), in order to produce a final source list. The sources from this list are further analyzed for clustering, extension, and variability. A background spectrum is determined and subtracted from the individual source spectra. Different models are fitted to these spectra.

HRI processing

is restricted to source detection. Sources are detected using several detection cells sizes. Multiple identifications of a source with different cell sizes are noted. Detected sources are checked for possible time variability.

In both cases a map of appropriate sources from the SIMBAD catalogue is produced to aid the observer in correlating the X-ray sources with previous known objects.