Volumetric Langmuir probe mapping of a transient pulsed plasma thruster plume

The triple Langmuir probe enables measurements of the transient plasma parameters over time at a point of interest. We demonstrate how these measurements can be easily combined to obtain a visualization of the overall plasma behavior of a pulsed plasma thruster. Through this, it is possible to identify features in the expansion of the plasma such as the canting angle of the plume. We also identified the early arrival of a negatively canted low-density plasma plume. The 2D profiles also reveal data that would otherwise be obscured by other planes in optical measurements.