Effect of low-frequency oscillation on plasma focusing in krypton hall thruster

In this work, a krypton Hall thruster is used to study the influence of low-frequency oscillation on the focusing characteristics of the plasma beam. The experiment results show that the plume divergence half-angle of the krypton thruster is sensitive to the low-frequency oscillation. Through monitoring the ionization process inside the discharge channel, it is found that the low-frequency oscillation leads to extending of the propellant ionization region downstream and, at the same time, the electron temperature is increased near the channel exit. As a result, the deviation of space potential lines from the magnetic linesisenhanced. These are the dominant physical mechanisms to affect the plasma beam focusing characteristics for the krypton Hall thruster.