Research On A Novel Compact Linac

Electron linac is a widely used device to generate high-power electron beam in industrial, electronic, medical and scientific research fields. Traditional linac consists of three main parts, including a microwave power source, an electron source and an accelerate structure. Also the traditional linac has complex structures and huge costs. With the purpose to simplify the system and control the budget, a brand new design of electron linac is invented. The new electron linac adopts the spent beam of a high power klystron as the source of electrons, thus eliminated the need for electron gun in the system, making the structure much simplified.Calculations, design works and fabrication of prototype have now been finished. We made some of the electrons to aggregate in the tube so that they have narrower phase width, thus we can omit the pre-bunching system. As for a prototype design, we adopted a KS4064-5MW klystron tube as both the power source and the electron source, and we used for travelling wave constant impedance accelerating structure in the design of the accelerating tube. Test results of the prototype showed that electron beams are produced as expected, verifying the feasibility of the design. Based on this, further researches are developed.We introduced tests and results of the prototype of the new electron linac, including standard running tests, tests of output beam characteristics in this article, followed by updates to the design according to simulation results of dynamics of macro-particle. Improvements and revises are made to the prototype in running tests, together with the establishment of safety and controlling sub-system to ensure the normal working environment and system safety.By changing the focus and thus selecting different operating points of the prototype, we measured and recorded the size, current, energy spectrum and emittance of the beam under these conditions. The maximum output current could reach 102 mA with centre energy of 10 MeV. This shows that the beam is satisfying and just as expected. According to the results, discussions of the usage in different industries as well as comparing with similar designs are given, followed by possible further updates and suggestions for system improvements. The PXR research based on this prototype is now being conducted, electron beams of 10 MeV energy were provided by the prototype linac for X-ray studies. Results show that our prototype is sufficient to supply the needed electron beams.All test results indicate that our new compact linac has sound performance and can meet the design requirements. The new linac has great application potential in various fields, such as industry radiation and medical treatments.