Investigating the particle beam properties of RF ion thruster with iodine propulsion

In this paper, we tried to perform a numerical simulation on the RF ion thruster optical system using the particle-in-cell method (PIC) to analyze the characteristics of the ion beam. In addition to significant ionization products, this contains small amounts of multivalent including I_b^+, I^(2+), I^3.The simulation results were obtained by comparing the characteristics of the beam with and without multivalent addition, the spatial distribution of ions, potential distribution, phase space distribution, beam current, and divergence angle. The results show that this program can correctly simulate the movement of ions in the optical system. With multivalent addition, the plasma potential increases, and the saddle point potential decreases, although the range of changes in the total potential distribution is limited. By adding polyvalence, the amount of charge increases slightly in proportion to the ionic group, as a result, the radiation current increases, and the divergence angle decreases slightly. Both special visits are slightly enhanced through appearance analysis. When the plasma density in the discharge chamber increases to about 2.4x1017m^(-3), the optical system reaches the beam extraction limit and the extracted beam current decreases instead of increasing with increasing plasma density. The simulation results can provide a reference for the design of the RF ion thruster optical system.