A new low-impedance high-intensity flash soft x-ray machine

A compact high-intensity flash soft x-ray machine in the nanosecond time region for shadowgraph applications in low-density matter as well as flash x-ray diffraction is described. The pulser consists of several 100 kV low-impedance coaxial pulse cables with the cable ends connected together to form closed loops. The pulser impedance can be varied stepwise between 6.7 and 0.67 Ω by increasing the number of loops from one to ten. This new technique facilitates appropriate tailoring of the anode-cathode geometry and opens the possibility for streak radiography when using long cables. Initial flash x-ray diffraction tests on a polycrystalline copper foil demonstrate the enhanced x-ray output relative to other machines. (author)