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Last modified: 22 January 2021

URL: https://cxc.cfa.harvard.edu/ciao/bugs/chandra_repro.html

Bugs: chandra_repro


Table of Contents

Caveats


Caveats

Deletes the NOM keywords [Updated] (22 Jan 2021)

The asp_offaxis_corr tool removes the RA_NOM, DEC_NOM, and ROLL_NOM keywords from the header of the aspect solution file. These keywords are used by some applications, such as marx.

Workaround:

To work around the problem, users can copy the *PNT keyword values to the *NOM values. For example:

bash$ for key in RA DEC ROLL
do
  val=`dmkeypar pcad_repro_asol1.fits ${key}_PNT echo+
  dmhedit pcad_repro_asol1.fits file= op=add key=${key}_NOM value=$val 
done

# - or - 

tcsh% foreach key (RA DEC ROLL)
  set val=`dmkeypar pcad_repro_asol1.fits ${key}_PNT echo+
  dmhedit pcad_repro_asol1.fits file= op=add key=${key}_NOM value=$val 
end

The asp_offaxis_corr tool is only run if asol_update=yes and if the data have not already had the correction applied in standard data processing or in repro-5. If the output directory does not contain a *_repro_asol1.fits file, then the asp_offaxis_corr was not run and this issue is moot.

Problem with large files  (18 Sep 2012)

chandra_repro uncompresses files into memory to be written back out to disk. With large files, this can exhaust system resources and cause the script to fail with a non-informative error message

Unable to read evt1 file
# chandra_repro (09 April 2012): ERROR read error

Workaround:

chandra_repro will use the uncompressed version of the file so the easiest work around it to gunzip the files before running chandra_repro

unix% gunzip primary/*gz secondary/*gz

dsAPEPULSEHEIGHTERR -- WARNING: pulse height is less than split threshold when performing serial CTI adjustment.

The following warning may be displayed when running chandra_repro on an ACIS observation

# acis_process_events (CIAO): The following error occurred 2 times:
    dsAPEPULSEHEIGHTERR -- WARNING: pulse height is less than split threshold when performing serial CTI adjustment.

As is discussed in the acis_process_events bug page, this warning can safely be ignored as long as the number of times printed is small compared to the total number of events.