Optical measurements of an electrothermal plasma

Abstract

Summary form only given. Presented in this paper are the results of optical measurements from electrothermal (ET) plasmas generated by firing Lexan samples in the SIRENS and PIPE facilities at North Carolina State University. Analyses of visible light emission from the ET plasmas at various energies (in the range of 0.5 to 6 kJ) were done to determine edge and core plasma densities and temperatures. Time-integrated measurements were made using a Tracor Northern Optical Multi-Channel Analyzer System (TN-6500), while time-resolved measurements were performed using Instruments S.A. H-20 monochromators and photomultipliers, looking at a single expected bright line. The transient current carried by the plasma through the Lexan sleeve was monitored by a Rogowski coil and Pearson current monitor. Applied potential was measured using a high voltage probe and chamber pressure measurements were done using Kistler piezo-electric pressure transducers. Fluctuations in the spectral intensity are being analyzed in order to relate them with the development of the electrical discharge.