Electromagnetic simulation of an electron cyclotron resonance ion source considering plasma effects

Abstract

The rare isotope accelerator complex for ON-line experiments uses an additional electron cyclotron resonance ion source to supply ions to users. This electron cyclotron resonance ion source can be derived from the 14.5 and 18 GHz driving frequencies. We performed an electromagnetic simulation of the plasma chamber prior to the engineering design phase. The 14.5 GHz-based electric field analysis of the model was extended to 18 GHz. We used the Drude model supported by the computer simulation technology microwave studio for the plasma simulation. The electrical field can be enhanced by accounting for the plasma effects of the Drude model despite the electric field in the vacuum being near the cylindrical wall. Therefore, we uncovered that the electric field distribution can be assessed in realistic situations by modifying the vacuum chamber shape to align with the plasma field inevitably formed by an externally applied magnetic field. In addition, the electric field in the near-axis region increased with optimization after modifying the cylindrical chamber into a plasma-shaped chamber.