Research And Design Of Novel Electron Cyclotron Auto-resonance Accelerator

Electron beams are widely used in high energy physics,biomedicine,environmental protection,industrial and agricultural production and other fields.High-current strength and high-power electron beams are urgently needed in applications such as industrial irradiation.However,currently the common industrial electron accelerators mainly include high-voltage accelerators and linear accelerators,which cannot meet the requirements of high energy and high current strength at the same time.The novel electron cyclotron auto-resonance accelerator（eCARA）uses an axial static magnetic field to achieve full-phase continuous cyclotron auto-resonance acceleration between electrons and the high firequency transverse electric field,breaking through the limitations of traditional accelerators,while having the characteristic of DC output and high energy output.eCARA is a high-power electron accelerator with great potential,which has important theoretical significance and application value.The axial static magnetic field and the acceleration cavity are the key to ensure the cyclotron auto-resonance acceleration of the electron,and they jointly determine the quality parameters of eCARA.However,the axial static magnetic field and the electron motion state affect each other.The magnetic mirror effect of the non-uniform magnetic field may even cause the electron to reverse;the quality parameters of eCARA are affected nonlinearly by the acceleration cavity parameters.Therefore,the optimization and design of axial static magnetic field and acceleration cavity are the essential point of eCARA research.This paper has conducted research of eCARA based on the circularly polarized TE₁₁ mode of a circular waveguide.The main contents include the analysis of the optimization method of the axial static magnetic field,the optimal design of the acceleration cavity,and the design of eCARA based on beam dynamics.The overall iterative optimization method of the axial static magnetic field:the stepwise iteration method is used to reveal the electron motion process under the ideal resonance axial static magnetic field;the overall iterative method is proposed according to the motion law.The results show that,compared with the ideal resonant axial static magnetic field,electrons are not easy to reverse in the quasi-resonant axial static magnetic field obtained by the overall iterative method,and a higher energy gain can be obtained.Optimization and design of eCARA standing wave cavity:Elucidating the mechanism of how the cavity parameters and the injection energy of electron to affect the acceleration process and the quality parameters of eCARA,providing certain theoretical support for the selection of key parameters of standing wave cavity under different application requirements,and establishing the design scheme of eCARA acceleration cavity;moreover completing the optimization and physical design of eCARA standing wave cavity.The design of eCARA based on beam dynamics:combining CST and PARMELA,the beam dynamics simulation analysis of the cyclotron auto-resonance acceleration process under the solenoid magnetic field is performed to verify the feasibility of the physical design of the acceleration cavity;the effect of the electron injection state error and axial static magnetic field error on the acceleration process is explored,clarifying the maximum error tolerance;considering the effect of the fringe field at the front end of the axial magnetic field,the analysis of two types of eCARA structures sets up a principle for the engineering design.Finally,on the basis of the above theoretical and simulation research,the design and simulation methods are applied to the flue gas irradiation treatment,which verified the reliability of the theoretical research and the feasibility of the design method.Besides,the physical design of an electron cyclotron auto-resonance acceleration section is completed,including the design of the standing wave cavity structure,the calculation of the quasi-resonant axial magnetic field and the eCARA layout design.For an input electron beam with 1 A and0.1 Me V,the electron capture rate of eCARA reaches 100%（full phase capture）,the average acceleration efficiency of the acceleration section is 85%,the average current and energy of the continuously self-scanning output electron beam are 1 A and 2.241 Me V separately,and the energy dissipation is 2.82%.