Ultrafast Electron Diffraction (UED)Ultrafast Electron Diffraction (UED)
is an indispensable tool for the study of molecular dynamics and
ultrafast chemistry. A number of research groups worldwide are
using GPT for the design of a variety of UED sources. Two samples are
shown below, a more detailed overview is given
here.
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Detailed GPT simulation results for a 100 fC ellipsoidal
100 keV electron bunch, that is subsequently recompressed to 30 fs by an
rf-cavity. Each and every electron has been tracked in 3D, through
realistic fields, including space-charge. |
Excellent agreement between experimental diffraction data
for a 5.4 MeV beam, and GPT simulation results. Published as
Ultrafast time-resolved
electron diffraction with megavolt electron beams by J. B. Hastings
et al. Please note that we are not directly involved in this project,
but we are impressed by the results. |
Design of the Alpha-X beamline |
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At Strathclyde University, Glasgow, a 4 year project
aims at the demonstration of controlled plasma acceleration, with the
final goal to produce coherent short wavelength radiation. The plot on the left shows the rf-photogun,
with inner dimensions designed by Pulsar Physics. |
Uniformly charged ellipsoidal (waterbag)
electron bunches |
 |
Uniformly charged ellipsoidal bunches, also known as waterbag
bunches, have linear self-fields in all coordinates. A practical method
to produce such bunches has recently been discovered. The plot on the left shows
a GPT simulation of a 'waterbag' bunch produced in a 1.5 cell
3 GHz cavity by a transversely shaped femtosecond laser pulse. |
Design of an Ultra-Cold-Atoms (UCP)
injector |
 |
Ultra-bright electron bunches can be created by
extracting a bunch from an ionized ultra-cold plasma. A large number of
GPT simulations have been performed to study the feasibility of this
approach. The plot on the left is an artist impression of the device currently
under investigation. |
OLD projects |
Design of the electron beam optics and radiation yield simulations
for the FZR Free-Electron-Laser |
 |
The Forschungs Zentrum Rossendorf (FZR) near
Dresden has recently built a superconducting linear accelerator (ELBE) to deliver intense
particle and radiation beams over a broad range. The (far) infrared part of the radiation,
from 5 to 150 µm, will be generated with free-electron lasers (FELs). The plot
on the left shows the spectral evolution during 100 passes of an electron bunch through
the undulator. |
A high-brightness DC/RF photo injector |
 |
This project, part of our PhD research, aimed
at investigating the feasibility of a high-gradient, 1 GV/m, pulsed-DC
accelerator directly followed by a state-of-the-art rf-booster. The
plot on the left shows the 2.5 cell booster cavity. |
Design of
an energy recovery system for a 12 A, 50-375 keV electron beam |
 |
The "Rijnhuizen" Fusion Free-Electron Maser (FEM) is the
prototype of a high power, 1 MW, electrostatic mm-wave source, tunable in the range
130-260 GHz. The electron beam line consists of an 80-keV, 12-A thermionic triode
electron gun, a 2-MV electrostatic accelerator, an undulator and a waveguide resonator
mounted in a high-voltage terminal, an electrostatic decelerator and a depressed
collector. This entire system has been simulated with the GPT code.
The plot on the left shows the depressed collector with sample electron trajectories. |
