Research On Low Energy Electron Linear Accelerator

Low energy electron Linac is one of the hotspots which is widely focused by many scholar recent years, it has shown its great application value in the field of industry, agriculture and medicine. Low energy electron Linac is developing rapidly mainly in two aspects so far, on the one hand, because the uniform beam energy, high beam quality, strong beam stability and the small cavity volume, low energy standing wave electron Linac has begun to gradually replace the low energy traveling wave electron Linac in medicine field, one the other hand, improve the conventional medical electron Liacac, make it become double beam electron Linac whitch is controlled by energy switch. Double beam electron Linac can output two electron beam whitch have different energy, it will achieve the precise radiotherapy.The key indicators of electron Linac is the output beam quality, include the beam spot size, the beam energy and so on. While, besides the input beam, the output beam quality also have a very close relationship with the electric field in the electron Linac, and the electric field in the electron Linac is closely related to the cavity size, so optimize the cavity size can improve the output beam quality.This paper first introduced the theory of electron Linac, briefly mentioned the acceleration principle of travelling wave and standing wave electron Linac, focus on the analysis of the electromagnetic field in standing wave electron Linac and some important parameter, introduced several typical standing wave electron Linac structure. Then we have optimized a single beam 6MeV magnetic coupled standing wave electron Linac, improved its electric field and the beam spot size, raised the output beam energy. Then we add a energy switch into a on axis coupling cavity of this 6MeV magnetic coupled standing wave electron Linac, change the original single beam electron Linac to the double beam electron Linac, and decrease the output beam energy to some extent. at last, by replace a on axis coupling cavity with side coupling cavity, put energy switch into the side coupling cavity, we decrease the output beam energy to KeV successfully.