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Radial profile of an extended source for Einstein IPC data.


Obtain a radial profile estimating the background level from a background map.


input files: xdata$snr.qp; xdata$snr_bbk.imh

intermediate file: broad.imh

output file: broad_cnt.tab

  cl> xray 
  xr> image  
  im> imcopy ``xdata$snr.qp[pi=2:10,bl=2]'' broad.imh # Selecting PI channels 2--10
                                                    # and spatial blocking factor 2
  im> bye                                             # Unload unnecessary packages 
                                                       # and load the relevant ones 
  xr> xspatial 
  xs> imcnts addbkgderr=no                        # Do not add the background error 
  source image file:  broad                                             # broad.imh
  source region descriptor:  a 251.5 256.5 0 25 n=5 
                              # 5 annuli at 251.5,256.5 0 to 25 pixel min/max radii 
  background image file or cts/pixel:  xdata$snr_bbk  
                                      # Broad band background map xdata$snr_bbk.imh 
  bkgd region descriptor:  a 251.5 256.5 0 25 n=5 
                                        # From the same region as the source counts 
  root name for output file [root_cnt.tab]:  broad   # Output file is broad_cnt.tab

Alternatively, the blocking and pi selection can be done as input to the task avoiding the creation of another data file.


input files: xdata$snr.qp; xdata$snr_bbk.imh

output file: broad_cnt.tab

  xs> imcnts addbkg=no                                      # Run the task as above 
                                                  # Do not add the background error 
  source image file: xdata$snr[pi=2:10,bl=2] 
          # energy filtering and spatial blocking on the original xdata$snr.qp file 
  source region descriptor:  a 251.5 256.5 0 25 n=5 
                    # 5 annuli centered at 251.5,256.5, 0 to 25 pixel min/max radii 
  background image file or cts/pixel:  xdata$snr_bbk  
                                      # Broad band background map xdata$snr_bbk.imh 
  bkgd region descriptor:  a 251.5 256.5 0 25 n=5 
                                        # From the same region as the source counts 
  root name for output file [root_cnt.tab]:  broad                  # broad_cnt.tab



rsdc@cfa.harvard.edu
1998-06-10