Mj. Deloos et al., THE GENERAL PARTICLE TRACER CODE APPLIED TO THE FUSION FREE-ELECTRON MASER, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 139(1-4), 1998, pp. 481-486
The fusion Free-Electron Maser (FEM) is the prototype of a high power,
electrostatic mm-wave source, tunable in the range 130-260 GHz. In or
der to achieve a high overall efficiency, the charge and energy of the
spent electron beam, i.e. the beam which leaves the undulator after i
nteraction with the EM-wave, has to be recovered. A 50% overall effici
ency is achieved, even for the maximum energy spread of 320 keV genera
ted in the undulator, using a collection system consisting of a decele
rator and a depressed collector. The General Particle Tracer code (GPT
) is being used as the major design tool for the whole fusion FEM beam
line: from the accelerator to the depressed collector. The high accur
acy, ability to include FEL interaction and full 3D treatment make GPT
the ideal choice for such a project. An overview of the separate sect
ions and the use of GPT for each part of the FEM is presented. GPT is
currently being applied to the design of the energy recovery system of
the fusion FEM, The first simulation results, including a 3D off-axis
bending scheme and scattered incident electrons, are shown. (C) 1998
Elsevier Science B.V.