XMM-Newton Science Analysis System: User Guide


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4.4.3 How to get pixels flagged "ON_BADPIX" back into the eventlist

Using the recommended selection expressions #XMMEA_EP and #XMMEA_EM, or even the more restrictive FLAG==0, pixels flagged as bad are not taken into account in the analysis. For specific circumstances it might be desired to revise a bad pixel flag and to make the pixel available again to the analysis using the task ebadpixupdate.

An important point regarding the bad pixels is that there are essentially three separate (though not exclusive) sets of bad pixels that must be dealt with. These are (1) bad pixels up-linked to the satellite and eliminated on-board, (2) bad pixels identified in the CCF but not up-linked, and (3) additional bad pixels associated with the particular observation in question. A corresponding list of bad pixels, individually for each CCD, is provided by the BADPIX**-extension tables inside the eventlist FITS-file.


next up previous contents
Next: 4.4.4 Filtering high background periods Up: 4.4 Filtering calibrated EPIC event lists Previous: 4.4.2 Filtering EPIC pn concatenated event lists
European Space Agency - XMM-Newton Science Operations Centre