Jet formation in low current x-pinch devices

Summary form only given. We report on the investigation of the jet formation mechanism in a 80 kA, 40 ns X pinch. Jets in various wire materials (aluminum, copper, molybdenum, nickel, stainless steel and tungsten) were probed with air-wedge interferometric and shadowgraphic techniques with a 3 ns pulse duration laser, and soft X-ray gated imaging (gate duration ~5 ns) with a wavelength <15 Aring. A qualitative difference in properties of the jets was observed as a function of wire material. The jets in tungsten X-pinches were well collimated similar to the observations made with conical wire arrays. Molybdenum and copper X-pinches show merging of the coronal plasma from the wires to the mid-axis of an X-pinch forming a Z-pinch column