Simulation software:
IMPACTT, written by Ji Qiang (LBNL), modified by Andreas Adelmann and Christof Kraus (PSI)
Visualization:
H5PartROOT
Setup: based on FELPM8400501
(Marco Pedrozzi)
Default parameters for IMPACTT:
time step:  1 ps^{*}  
number of particles:  100k  
mesh size:  32 × 32 × 32  
current:  0.329 Amp^{**}  (= 5.5 A * 40 ps * 1498.95 MHz) 
kinetic energy:  500 keV 
case 1  case 2  case 3  case 3a  
standard plot: emittance and RMS beam size (ROOT macro) 




comparison to Homdyn and GPT (ROOT macro) 




slice study (emittance and rms beam size) (ROOT macro) 




B field scan (python script, ROOT macro) 



(see case 3) 
misalignment study (python script, ROOT macro) 




movie (mpeg) 
IMPACTT simulation for case 1: comparison between simulations with time step 1 ps (0.1 ps for the first 15 mm) and 0.1 ps (0.01 ps for the first 15 mm). There is no perceptible difference. 
Short pulse (20 µJ) has 6.5 ps width (Gaussian sigma). With IMPACTT, we can only simulate uniform time distribution. I therefore approximate the 6.5 ps Gaussian sigma pulse with a 22.5 ps uniform pulse.
I played around with SP1 and SP3/SP4 (i.e. using only two solenoids at a time) and tried to find settings where there is a clear minimum in projected emittance, roughly coinciding with the beam waist following the solenoids.
The current is 1 A.
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