Low Frequency Dynamical Behavior Of The Plasma At The Exit Plan Of A Hall Effect Thruster

A large research programme on Hall thrusters has been initiated in France in 1996. This programme includes modelling, as well as theoretical and experimental approaches. These researches are coordinated in the frame of a national Research Group. Recent results obtained at the laboratoire d'Aerothermique taking part to the activities of this group are presented. A short description of electric propulsion and especially the behaviour of a Hall Effect Thruster are presented in the first part of this paper. In the second part, experimental time resolved measurements performed by means of electrostatic probe are presented to show the dynamical behaviour of electron characteristics and compared with the recorded discharge current and potential. These results describe to ion and electron properties in the plasma flow in the surroundings of the thruster channel exhaust.