Experimental determination of plasma armature properties using RGS-II, a railgun simulator

Summary form only given, as follows. A description is given of an experimental device, RGS-II, that provides a moving plasma armature without a projectile, at current and velocity levels similar to those in railguns, by simulating the mass of the projectile with the magnetic back pressure of a muzzle-fed current pulse. This device is ideally suited for the implementation of diagnostic techniques because it lacks a projectile in the bore. Several diagnostic techniques have been used on the system to create a database of information on high-current, moving plasma armatures. In addition to the standard arc current and voltage probes, the railgun simulator used magnetic field probes to determine the plasma velocity and current density profile, laser transmission ports to determine the optical transmission properties of the plasma, and time-resolved interferometry and spectroscopy to determine plasma density, temperature, and primary plasma constituents. The data allow a preliminary picture to be drawn regarding the moving plasma arc and its properties.<>