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Basic scan analysis¤

Using the plot_analysis/plot_properties.PlotProperties class (see the example script), the parameter scan can be quickly analyzed and the effect of the scanned parameter on bunch properties plotted. Best used when the plotting script is called automatically after the scan is complete.

Plots directory¤

A plots/ directory will be created in the working directory. Within this plots/ directory, several directories will be created based on how many setup settings were scanned at the same time, to show the dependency of the bunch parameters on this setting. In these directories, the plots are located along with an excel file data.xlsx containing the data used to create the plots. 

plots/
    setting1/
        data.xlsx
        plot1.png
        plot2.png
        ...
    setting2/
        data.xlsx
        plot1.png
        plot2.png
        ...
    ...

The following plots are included:

  • Active particle ratio_zpos_end.png plot of the ratio of active (not lost) particles, 1 means no particles were lost in the simulation.
  • Beam size (z_rms)_zpos_end.png plot of the rms bunch length.
  • energy_spread_zpos_end.png plot of the rms energy spread.
  • energy_zpos_end.png plot of the particle energy with the rms energy spread as the error bars.
  • x_emit_zpos_end.png plot of the rms normalized transverse emittance in the x plane.
  • x_rms_zpos_end.png plot of the rms transverse bunch size in the x plane.
  • xBar_rms_zpos_end.png plot of the rms beam divergence in the x plane.
  • y_emit_zpos_end.png plot of the rms normalized transverse emittance in the y plane.
  • y_rms_zpos_end.png plot of the rms transverse bunch size in the y plane.
  • yBar_rms_zpos_end.png plot of the rms beam divergence in the y plane.

Info

The plot name contains the \(z\) coordinate (zpos). In the case presented above, the bunch parameters were evaluated at the end of the simulation, which is the default setting for most optimization scripts. It can be changed when plotting manually in the plot_analysis/plot_properties.PlotProperties class definition.

Analysis output file¤

The scan summarizing data that were used for the plotting is saved in the plots directory as an excel (.xlsx) file. Each simulation run is represented as a row. The columns are described in the table bellow

Column Description
Index Index column.
run Run number
scanning_parameter Value of the parameter that was scanned.
energy Bunch energy.
energy_spread Rms energy spread.
x_emit Rms normalized transverse emittance in the x plane.
y_emit Rms normalized transverse emittance in the y plane.
x_rms Rms transverse bunch size in the x plane.
y_rms Rms transverse bunch size in the y plane.
xBar_rms Rms beam divergence in the x plane.
yBar_rms Rms beam divergence in the y plane.
Active particle ratio Ratio of the active particles (those not lost during the simulation). 1 means no particles were lost.
Beam size (z_rms) Rms bunch length.

The input file can be loaded into python using the pandas data analytics library as follows

import pandas as pd 

df = pd.read_excel("data.xlsx", index_col=0)
Last update: September 14, 2023
Created: September 14, 2023