Rapid Joule heating by a large current flowing through a small diameter wire, can be used to create a high temperature {dollar}{lcub}>{rcub}10sp5{dollar} K, high density {dollar}rm{lcub}sim{rcub}10sp{lcub}22{rcub}/cmsp2,{dollar} plasma. The combination of high density and high temperature attracted research interest in creating thermonuclear fusion conditions in the laboratory. Gerber and Sethian{dollar}sp9{dollar} (1990) discharged current through a frozen deuterium fiber producing 10{dollar}sp9{dollar} neutrons per discharge.; It was suggested by Raman et al.{dollar}sp{lcub}20{rcub}{dollar} (1995), that the explosion of a fiber as the target in a Staged Z-pinch configuration could provide better fusion conditions than those observed in the experiments of Gerber and Sethian.{dollar}sp9{dollar}; The idea behind the staging concept is to explode a deuterium fiber on axis in a standard annular gas puff Z-pinch configuration, prior to initiation of the main Z-pinch discharge. Calculations show that the self generated azimuthal magnetic field produced by the fiber will be compressed during the implosion of the highly conducting plasma annulus. The resulting magnetic flux compression is estimated to increase the current through the fiber faster than the time it takes for disruptive MHD instabilities to grow.; Two main diagnostics were developed to image such high density, fast time scale processes. A sub-nanosecond, ultraviolet, atmospheric pressure nitrogen laser system and a 100 kV, 15-40 ns pulsed bremsstrahlung x-ray source were designed and built at UC Irvine. Lateral shearing interferometry was used to analyze the high voltage breakdown process in exploding wires in vacuum.; These diagnostics were used for imaging a series of exploding metal wire experiments, to determine important Staged Pinch target preparation issues. X-ray and laser absorption as well as interferometric images are presented of copper and iron wires exploded in vacuum at a maximum current level of 10-12 kA. Clear imaging and a general discussion of the breakdown phenomena are presented. Striations were observed by both the x-ray and laser diagnostics, along the length of the wires. Each diagnostic is discussed in detail in separate appendices.; This work suggests that proper surface preparation improves the energy coupling into an exploding wire.
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