Time-Resolved Radial Velocity Profile Measurements on a Coaxial Plasma Accelerator

We report on measurements of the radial profile of the axial velocity component of a gas-fed shear-flow stabilized coaxial Z-pinch plasma accelerator operating in a deflagration mode. Doppler-shifted axially-directed spectral line emission of hydrogen and impurities are recorded from the plasma jet generated by the Stanford Coaxial High ENerGy (CHENG) device using a Raman monochromator paired with a high frame rate (10 MHz) intensified camera allowing for resolutions of up to 100 ns. This configuration affords single-shot video of 1D-1V dynamics (time-dependence) of the Stark-broadened/Doppler shifted spectral lines to determine axial velocity, temperature, and electron number density as a function of radial position. Derived velocities are compared to time-of-flight velocity measurements taken on the same device for the same conditions.