ixpepipe

Contributed by: Douglas Swartz & Sudip Chakraborty

Latest update: Apr 10 2026 initial release

ixpepipe is a bash shell script that executes a series of FTOOLS commands to process an IXPE Level 1 file event file to produce a new Level 2 event file. The script requires a valid observation UID, a detector unit number, the pathname of a directory containing the subdirectory UID (that contains IXPE science and housekeeping data files in the IXPE archive directory structure), the (optional) pathname of a directory to place output (default is the current working directory), and the (option) to retain pipeline intermediate files including FTOOLS task log files (in a zip'd format; default is to not retain the files). All input parameters can be entered on the command line or they will be prompted for interactively. A CALDB must be configured and the IXPE mission CALDB installed. The mission-specific IXPE FTOOLS must be installed.

Example 1:

Reproduce the Level 2 file for UID 04004001, DU 2:

 ixpepipe 04004001 2 /data/ixpe/obs/

will place resultant file, named level2_04004001_det2.fits, in the current working directory and delete all intermediate files created during the pipeline processing. The directory /data/ixpe/obs/04004001/ must exist and contain subdirectories /event_l1/, /event_l2/, /auxil/, and /hk/ populated with IXPE archival data.

Example 2:

Reproduce the Level 2 file for UID 04004001, DU 3, and put the results in directory mydir:

 ixpepipe 04004001 3 /data/ixpe/obs/ mydir y

will place the resultant file, named level2_04004001_det3.fits, in directory mydir and save all intermediate files created during the pipeline processing in file mydir/ixpe04004001_det3_00_intermediate.zip. If mydir does not exist it will be created. The zip'd file name portion _00_ indicates the observation segment number; in this case the observation is not segmented. If the observation were segmented, there will be a zip'd file for each segment labeled with _01_, _02_, etc.

Example 3:

Reproduce the Level 2 file for the segmented observation UID 04003999, DU 2:

 ixpepipe 04003999 2 /data/ixpe/obs/

will place the resultant file, named level2_04003999_det2.fits, in the current working directory and delete all intermediate files created during the pipeline processing except the Level 2 segment files level2_04003901_det2.fits and level2_04003902_det2.fits.

Example 4:

Produce a Level 2 file for UID 04004001, DU 2, using a spurious modulation map other than the default map contained in the CALDB:

 pset ixpeadjmod spmodfile=myspmodfile.fits
 ixpepipe 04004001 1 /data/ixpe/obs/  
 pset ixpeadjmod spmodfile=CALDB

will place the resultant file, named level2_04004001_det1.fits, in the current working directory and delete all intermediate files created during the pipeline processing. The FTOOL ixpeadjmod task will use the spurious modulation map parameter value, myspmodfile.fits, within the ixpepipe processing and the value will be reset to CALDB afterwards. In this case, CALDB is the default value, so an equivalent (though not identical) command sequence would be:

 pset ixpeadjmod spmodfile=myspmodfile.fits
 ixpepipe 04004001 1 /data/ixpe/obs/  
 punlearn ixpeadjmod

Example 5:

Reproduce the Level 2 file, interactively:

 ixpepipe

will prompt for (1) UID, then (2) DU number, (3) directory containing the UID subdirectory (that contains the archived data for UID), (4) output directory (default current working directory), and, (5) whether or not to keep intermediate processing files (y/n; default n).