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XMM-Newton Science Analysis System

ebkgreg (ebkgreg-0.8) [xmmsas_20211130_0941-20.0.0]


The source image may be input in detector or sky (X/Y) coordinates. The task expects to find astrometry keywords in a certain part of the primary header and will exit with an error if the keywords are not found. Standard images produced by evselect and xmmselect and the pipeline will process ok. The background spline maps produced by the pipeline source detection chain and the exposure maps produced by eexpmap need to be pre-processed before they can be used within ebkgreg (see ecoordconv task).

That image has to contain keywords INSTRUME, DATE-OBS, RA_PNT, DEC_PNT and PA_PNT. It also needs to contain the WCS keywords, CRPIX1 etc. to allow conversion to image pixels. A further set of keywords, REFXCRPX etc. allow translation to an X/Y tangential plane coordinate system.

XMM-Newton SOC -- 2021-11-30