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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 *** <TJ HELP PLEASE> in the files xtcavDark.py, xtcavLasingOff.py, xtcavLasingOn.py.

Quickstart

[ Quick description of the dark, lasing off, data processing steps, 2-3 sentences ]XTCAV analysis is a three step process involving "dark", "lasing off", and "lasing on" runs. First, we process dark runs, which are runs without any electron bunches. We take the average of a series of dark run images to get the general pixel values of the camera background. We can then subtract this "average image" from the lasing on and off runs to get a closer approximation of the actual energy of the electron bunches. We then process the lasing off runs, which are images of electron bunches without any lasing. We take a series of these images, subtract the average background (from previous step), and zero-out all noise around the region of interest. From this cleaned up image, we can calculate the electron current, the energy dispersion and center of mass, and other physical properties of the electron bunch. We then cluster together these lasing off images into an (optimally or manually chosen) number of groups based of of the electron current. The properties of these profiles are then averaged to create an aggregate lasing off profile. This is done to help reduce noise in the image as well as to speed up the process of choosing a lasing off reference in the lasing on analysis (discussed next). For the lasing on runs, we process each image individually in a similar manner to the lasing off images. Once we calculate the physical properties, we choose an aggregated lasing off profile with the most similar electron current. Then, using either the energy loss or energy spread methods, we can calculate the power of the electron bunch.  

Then, for each of the following, an example (from amox23616) of the command used and output:

Dark

xtcavDark amox23616 104 --max_shots 400

Lasing Off

Lasing On

Analysis Setup

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