Diagnostics and analysis of incident and vapor shield plasmas in PLADIS I, a coaxial deflagration gun for Tokamak disruption simulation

Tokamak disruption simulation experiments have been conducted at the University of New Mexico using the PLADIS I plasma gun system. Earlier work had characterized the plasma-surface interaction in terms of parameters such as incident energy from bucket calorimeter measurements and rough measurements of beam area from flat damage targets. A variety of new plasma diagnostics have been used to further investigate the characteristics of the incident plasma beam and vapor shield plasma in a simulated tokamak disruption. These diagnostics have included laser interferometry, two-color pyrometry, emission spectroscopy, and other methods to quantify the characteristics of the incident and vapor shield plasmas of a simulated tokamak disruption. The synthesis of different beam area measurement techniques is used to determine the radial structure of the plasma beam. Vacuum ultra violet spectroscopy is used to determine the thickness and internal structure of the vapor shield plasma. Results from two-color optical pyrometry and surface pressure measurements are used to determine the dynamics of vapor shield formation. Index Terms - Ablation, cooperative tokamak disruption simulation experiments, dense vapor shield, disruption-like heat flux, energy fluxes, graphite erosion, graphites, heat load material, impurity content, ITER program, PLADIS plasma gun simulator, plasma diagnostics, plasma facing components, plasma facing component materials, plasma flow, plasma stream impact, plasma wall interactions, tokamak disruption, tokamak disruption simulation experiments, tokamak disruption simulations, transmission grating, vacuum ultraviolet spectrographs.