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These scripts use some XTCAV data that was made public so they should be runnable by all users.  The scripts can be found in /reg/g/psdm/tutorials/examplePython/xtcav/ in the files xtcavDark.py, xtcavLasingOff.py, xtcavLasingOn.py.  They analyze a minimal number of events to make them run fairly quickly.

Analysis Setup

Two things must be done before XTCAV analysis will function: a "dark run" must be analyzed to get the pedestal values for cameras, and a "no lasing" run must be analyzed to generate sets of "no lasing" images (the latter is quite a complex process).  Note that for demonstration these first two scripts write constants to a "local" calibration directory called "calib".  For a real-experiment you won't need these lines because you will have permission to write to your official experiment calibration-constants directory.

An  An example of a dark-run analysis is in /reg/g/psdm/tutorials/examplePython/xtcav/xtcavDark.py:

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This script can be quite slow.  It can be easily run in parallel by submitting a parallel MPI job to the batch system as described here, however you should change the above script to increase the "maxshots" parameter (so that each core has at least 1 shot to process).  People often use ~1400 shots for this.

Once the dark/lasing-off analysis has been completed, users can analyze the lasing-on events using a standard psana-python script similar to the one below.

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This script assumes that dark/lasing-off data has been analyzed (see above).   This Unlike the previous two scripts it reads dark/lasing-off constants from the official calibration-directory.  This script can be found in /reg/g/psdm/tutorials/examplePython/xtcav/xtcavLasingOn.py:

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