Microsecond conduction time POS experiments

The plasma opening switch operation (POS) was studied by optical diagnostic s, such as laser interferometry and spectroscopy. The characterization of t he plasma source (cable plasma gun) allowed us to determine initial plasma conditions for the switch. The process of the vacuum gap formation in a mic rosecond plasma opening switch was also investigated. Time- and spatially-r esolved density measurements are performed in the POS, showing the density drop during switch-opening almost in the whole interelectrode gap. The dens ity diagrams are compared to major switch characteristics, such as conducti on time and load current dI/dt. The study of spectral line intensities from the cable gun plasma showed that CII line intensity corresponds in time wi th plasma density measured by an interferometer. The intensities of carbon spectral lines tend to drop during switch-opening that substantiates interf erometry measurements. (C) 1999 Elsevier Science S.A. All rights reserved.