Parameter optimisation design of helicon wave plasma source in High Magnetic field Helicon eXperiment

Based on the High Magnetic field Helicon eXperiment (HMHX), considering parabolic distribution and Gaussian distribution of radial plasma density, the HELIC code was used to study the parameter optimisation design of a helicon wave plasma (HWP) source. Some parameters (antenna type, radio frequency, discharge gas, plasma radius, magnetic field) were selected. The results show that a half-helix antenna is the excitation antenna and a frequency of 13.56 MHz is the most commonly used power source for HMHX. Argon and nitrogen are selected as discharge gases to achieve the best effect of power deposition. In order to realise hydrogen–HWP discharge, a new antenna with plasma radius of 10.5 mm and antenna radius of 13.5 mm can be designed. For the new antenna, when the magnetic field intensity is 1000 Gs, the best discharge effect can be achieved. The results of this paper can provide guidance for the design of a plasma source for HWP discharge under different conditions in the future.