Electromagnetic Simulation Design of ECR Proton Source for BNCT Accelerator

Based on the advantages of high beam current, high brightness, high reliability, high utilization rate, easy maintenance, and compactness, electron cyclotron resonance (ECR) proton source is used on the accelerator for boron neutron capture therapy (BNCT). With code CST, the 2.45 GHz ECR proton source was designed and optimized. The optimized size of plasma generator chamber is 101.12 mm×45.00 mm, and size of the ridge waveguide coupler was optimized. Compared with normal waveguide coupler, the electric field in the plasma generator chamber with ridge waveguide coupler is enhanced to 4.5 times. Parameters of extraction electrode structure were optimized by code Opera-3D, and size and voltage were given. In addition, the magnetic system was preliminarily designed and magnetic distribution was optimized. The results are important reference for proton source development.