Analysis of the characteristics of the plasma of an RF driven ion source for a neutral beam injector

A radio frequency (RF) driven ion source is a very important component of a neutral beam injector for large magnetic confinement fusion devices. In order to study the key technology and physics of an RF driven ion source for a neutral beam injector in China, an RF ion source test facility was developed at the Institute of Plasma Physics, Chinese Academy of Sciences. In this paper, a two-dimensional fluid model is used to simulate the fundamental physical characteristics of RF plasma discharge. Simulation results show the relationship of the characteristics of plasma (such as electron density and electron temperature) and RF power and gas pressure. In order to verify the effectiveness of the model, the characteristics of the plasma are investigated using a Langmuir probe. In this paper, experimental and simulation results are presented, and the possible reasons for the discrepancies between them are given. This paper can help us understand the characteristics of RF plasma discharge, and give a basis for further R&D for an RF ion source.