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XMM-Newton Science Analysis System


badpixfind (badpixfind-1.41) [xmmsas_20230412_1735-21.0.0]


Algorithm

   subroutine badpixfind

    * Get input file, parameters, instrument, mode, ccdid, exposure, obsid 
    * set state of CAL
    * exit if no modes chosen (searchbadpix=N, userflagbadpix=N)
    * check userflagbadpix lists are of equal size
    * open output file
    * get uplinked bad pixels from CCF
    * get `image' sizes and origin values, start times and end times
    * form images in memory from input events file, selecting energy band if 
        required (in case of MOS, call pattern backprojecting and selecting 
        subroutines to get true image)
    * if MOS and flicker, get timestep indices - form `flicker' array    
    * calculate and output (to screen) initial pixel statistics 
    * if required, calculate and output (to screen) initial column statistics 

    * call mode_1 (searchbadpix), and mode_1 column analysis 
        (withbadcolumnsearch) (+ PSF comparison), if required.
        set of procedures (max/min threshold) techniques performed on image
        * if hot pixel found - check edge effects - compare with PSF, using 
          only good pixels (no uplinked or found bad pixels)  
          - return measure of comparison with PSF 
      * if requested, perform flickering analysis (low and high count cases)
    * Obtain badpix set (for mode1) (RAWX, RAWY, Y-extent, fault type) 

    * calculate and output (to screen) new pixel statistics 

    * call mode_2, if required  
        explicitly flag pixels as bad, the user having given RAWX, RAWY, 
        Y-extent and type of fault as input lists
    * Obtain badpix set (for mode2) (RAWX, RAWY, Y-extent, fault type) 

    * Check badpix sets (mode1 and mode2) for redundancy/duplication
    * calculate and output (to screen) final pixel statistics 
    * Combine individual badpix sets into output file 
    * Create, if required, bad pixel map (with optional FOV masking) 
    * Add attributes and history
 
   end subroutine  badpixfind



XMM-Newton SOC -- 2023-04-16