Cutting torch 12 Nozzle exits Fluid dynamics 8 High energy densities 8 Nozzles 8 Cavity resonators 6 Electric fields 6 Electric potential 6 Plasma diagnostics 6 Plasma temperature 6 Plasmas 6 Arc plasma 4 Average field 4 Bandpass filters 4 Biasing voltages 4 Breakdown threshold 4 Carrier concentration 4 Cold ions 4 Drift diffusion 4 Electron densities 4 Electron density measurement 4 Electron temperature 4 Gas breakdown 4 Hydrodynamic instabilities 4 Hydrodynamic model 4 Ion collisions 4 Ion density 4 Ion velocity 4 Ions 4 Light fluctuation 4