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"""
Example 12

- EEHG (echo enhanced harmonic generation) FEL
- 3-stage simulation: 1st/2nd modulator, 3rd radiator
"""

import sys
isjupyter = "ipykernel" in sys.modules

import simplex 

if isjupyter:
    simplex.Start(mode="c") 
    import plotly.io as pio
    pio.renderers.default = "notebook" # to enable exporting as an HTML file
    from IPython.display import display, HTML
else:
    simplex.Start()

# open "sample_mod.json" to simulate the particle motion in the modulator 1&2
simplex.Open("sample_mod.json")

# reduce the bunch charge and length
simplex.Set("ebeam", "bunchleng", 5e-6)
simplex.Set("ebeam", "bunchcharge", 0.05)

# reduce the seed power
simplex.Set("seed", "pkpower", 5e7)

# increase particles/beamlet to cover up to 50th harmonic
simplex.Set("condition", "particles", 102)

# shrink the simulation temporal window
simplex.Set("condition", "simrange", [-12e-6,12e-6])

# dump the particle data at the final step
simplex.Set("datadump", "particle", True)
simplex.Set("datadump", "expstep", "Final Step")

# start simulation in the 1st modulator
simplex.StartSimulation(folder="./output", prefix="sample12", serial=1)

# verify the energy modulation
if isjupyter:
    display(HTML("<h2>Particle distribution at the 1st modulator exit with R<sub>56</sub>=5mm"))
    simplex.PostProcessCLI.RunDataProcessing(
        item="Particle Motion", timerange="Set Window", timewindow=[0, 0], r56pp=8.4e-3, 
        config={"type":"Symbol", "size":1})
else:
    simplex.PostProcess.SetDataProcessing("item", "Particle Motion")
    simplex.PostProcess.SetDataProcessing("timerange", "Set Window")
    simplex.PostProcess.SetDataProcessing("timewindow", [0, 0])
    simplex.PostProcess.SetDataProcessing("r56pp", 8.4e-3)
    simplex.PostProcess.RunDataProcessing()
    simplex.PostProcess.SymbolPlot(1)
    simplex.PostProcess.DuplicatePlot("Particle distribution at the 1st modulator exit with R<sub>56</sub>=5mm")

# 2nd modulator
# import the particle data at the 1st modulator exit with R56=8.4mm
simplex.Set("condition", "simoption", "N.A.") # disable any option to enable importing SIMPLEX output (next command)
simplex.Set("ebeam", "bmprofile", "SIMPLEX Output")
simplex.Set("ebeam", "r56", 8.4e-3)
simplex.Set("spxout", "spxfile", "./output/sample12-1.json")
simplex.Set("seed", "pkpower", 5e6)
simplex.Set("seed", "timing", -4)

# start simulation in the 2nd modulator
simplex.StartSimulation(folder="./output", prefix="sample12", serial=2)

# verify the energy modulation
if isjupyter:
    display(HTML("<h2>Particle distribution at the 2nd modulator exit with R<sub>56</sub>=0.24mm"))
    simplex.PostProcessCLI.RunDataProcessing(r56pp=3.6e-4, config={"type":"Symbol", "size":1})
else:
    simplex.PostProcess.SetDataProcessing("r56pp", 3.6e-4)
    simplex.PostProcess.RunDataProcessing()
    simplex.PostProcess.SymbolPlot(1)
    simplex.PostProcess.DuplicatePlot("Particle distribution at the 2nd modulator exit with R<sub>56</sub>=0.24mm")

# open "sample_rad.json" to simulate the harmonic generation in the radiator
simplex.Open("sample_rad.json")

# import the simulation result at the 2nd modulator exit
simplex.Set("ebeam", "bmprofile", "SIMPLEX Output")
simplex.Set("spxout", "spxfile", "./output/sample12-2.json")

# shorte period and more segments for higher harmonics
simplex.Set("undulator", "lu", 30)
simplex.Set("undulator", "segments", 8)

# enable "Higher Precision" to evaluate the bunch factor more precisely
# needed because the beamlet expands across a large number of slices
simplex.Set("condition", "hpcond", True)
simplex.Set("condition", "step", 10)

# shrink the simulation temporal window
simplex.Set("condition", "simrange", [-5e-6,5e-6])

harmonics = [24, 48] # evaluate the 25th and 50th harmonics
nr = 5 # number of R56 scan for each harmonics
r56 = [3.3e-4, 3.7e-4] # scan R56 from 330um to 370um
fr = 0.01  # spectral range (+-1%)  to show

for harmonic in harmonics:
    simplex.Set("felprm", "l1st", 266/harmonic)
    simplex.Scan("ebeam", "r56", r56[0], r56[1], nr, folder="./output", prefix="sample12", serial=harmonic)
    datanames = []
    enh = 1240/266*harmonic # central photon energy
    for sn in range(1, nr):
        datanames.append("sample12-"+str(harmonic)+"_"+str(sn))
    if isjupyter:
        display(HTML("<h2>Spectrum of "+str(harmonic)+"th-harmonic radiation"))
        simplex.PostProcessCLI.Plot(data=["sample12-"+str(harmonic)+"_0", *datanames], item="Spectral Profile",
            config={"xrange":[enh*(1-fr),enh*(1+fr)]})
    else:
        simplex.PostProcess.SelectData("sample12-"+str(harmonic)+"_0")
        simplex.PostProcess.Plot("Spectral Profile")
        simplex.PostProcess.ComparativePlot(*datanames)
        simplex.PostProcess.PlotRange(x=[enh*(1-fr),enh*(1+fr)])
        simplex.PostProcess.SetSlide(-1)
        simplex.PostProcess.DuplicatePlot("Spectrum of "+str(harmonic)+"th-harmonic radiation")

if not isjupyter:
    input("Completed. Press enter to exit. ")
    simplex.Exit()

Particle distribution at the 1st modulator exit with R56=5mm

Particle distribution at the 2nd modulator exit with R56=0.24mm

Spectrum of 24th-harmonic radiation

Spectrum of 48th-harmonic radiation

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