Fast pressure probe measurements of a high-velocity plasma plume

This article reports measurements of stagnation pressure on a contoured coaxial gun, now installed at the Maryland Centrifugal Experiment [R. Ellis et al., Phys. Plasmas 12, 055704 (2005)]. The impact of the plasma on the stationary probe is consistent with adiabatic compression and supersonic flow. Measured pressure signals are consistent with a shock traveling at 110 km/s and a following flow with speed of 90 km/s. At late times, the pressure profile is consistent with an adiabatically expanding plasma that fills the vacuum chamber.