Measurement of the mass density evolution of wire explosion using X-ray backlighting

Summary form only given. The evolution of single-wire and dual-wire Z-pinch of 8μm-W were investigated by X-ray backlighting using the X-pinch which radiated a soft X-ray source. The experiments were carried out on the pulsed power generator PPG-I (400kA/500kV/100ns) which was designed and constructed by Department of Electrical Engineering of Tsinghua University. In order to scale the mass distribution at different explosion time, a mass step wedge including eight tungsten layers was fabricated and inserted between the object Z-pinch and the X-ray film. By a large number of imaging experiments, the physical images of the plasma merging, the coronal plasma formation and development of the instabilities of Z-pinch and some important parameters like mass ablation ratio and core expansion ratio were obtained. The mass density distributions at different explosion time were drawn based on the x-ray photos of 8μm-W and step wedge. The conductance curve of time-dependence of 8μm-W was also calculated using waveform of voltage and current.