ICRF Wave Propagation and Absorption in a Microwave Discharge Ion Thruster

Preliminary experiments are made on the EICR plasma thruster which can generate plasma with ECRH (Electron Cyclotron Resonance Heating) and accelerate ions with ICRFPI (Ion Cyclotron Range of Frequency Heating). A set of plasma diagnostics is being developed and installed. The electron temperature T_e, electron density n_e and ion temperature T_i were measured in our device. To examine ICRF wave propagation in the plasma, the magnetic fields were measured and the results show that the excited waves were attenuated before reaching the ICR layer. Moreover, ICRF wave absorption and propagation were calculated with an ICRF code. The strong energy absorption in the plasma was obtained at the ICR layers.