Pulsed Power Driven Flash X-ray Sources for the Hydrus Project at AWE

Summary form only given. The Hydrus project will provide an enhancement of the flash radiographic diagnostics available in the Hydrodynamics Department at AWE as part of new facilities for hydrodynamics research. The X-ray sources for the experiments carried out at AWE are provided by focused electron beam diodes driven by pulsed power accelerators. The most attenuating objects to be radiographed require an X-ray spectrum and dose that can only be provided by pulsed power machines operating at 7 to 14 MV. A design for a 14 MV IVA (induction voltage adder) has been completed by L3 Communications Pulse Sciences for AWE and three such machines are about to be manufactured to provide the main radiographic capability in the new facility. Research currently being conducted by AWE and international collaborators aims to also develop improved electron beam diodes to meet the requirements for higher radiographic resolution being demanded. Other experiments performed at AWE require a softer X-ray spectrum and hence a lower voltage pulsed power driver, two of which will be provided in a second area of the same facility. It has been determined that the optimum radiographic source will have a sub-100 ns pulse , a diameter of 1 mm or less, an X-ray dose of at least 15R at 1 metre and an X-ray spectrum end point energy of 1-1.5 MeV. An electron beam diode that has demonstrated performance o f this order is the plasma filled rod pinch driven by the Gamble II accelerator at NRL. After a concept study and discuss ions with possible vendors it has been decided procure two machines similar in performance to Gamble II. They will feature a Marx generator charging a single water pulse forming line which will in turn drive the diode via a 3 ohm water insulated output line.