Time-resolved laser-induced fluorescence measurements in the plume of a 6 kw Hall thruster with unperturbed oscillations

We present results from interrogating the time-resolved ion velocity distribution in the plume of a 6 kW laboratory Hall thruster with laser-induced fluorescence (LIF). To our knowledge, these are the first measurements of time-resolved ion velocity distribution on completely unperturbed Hall thruster operating conditions. To date, time-resolved LIF measurements have been made on Hall thrusters with oscillations modified to be amenable to either an ensemble average in the time domain [1,2] or a heterodyne approach [3]. Each case relied on active perturbations in either discharge current [1], hollow cathode keeper potential [2], or anode potential [3].