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Wire array z-pinches are the world's most powerful laboratory x-ray source, however the large volume required for them to work efficiently requires the use of a large hohlraum for inertial confinement fusion applications. This hohlraum size limits the temperature achievable using present pulsed power capabilities. Whilst work is continuing to improve the efficiency of cylindrical wire arrays, an alternative is to use an array configuration that is better suited to a smaller hohlraum. Radial wire arrays have been shown to have similar emitted power and radiated energy to cylindrical wire arrays, however occupy a volume which is a factor of >4 smaller. We will discuss plans for radial wire array experiments on the multi-MA Saturn facility at Sandia, along with the results of MHD simulations and initial data.

Abstract. Polymorphic phase transitions in metals have been investigated for a long time under dynamic loadings through usual dynamic compression diagnostics such as velocity and temperature measurements. Such measurements were valuable for revealing the key role of kinetic effects in most phase transition mechanisms. However, the information extracted was mostly macroscopic. Obtaining direct insight about the crystallographic structure under dynamic loadings is critical for understanding mechanisms governing shock-induced structural changes. For example, in order to evidence a mixture phase or to determine the time scale of a transition, structural information may be extremely valuable. Over the last 20 years a significant number of X-ray diffraction experiments were carried under dynamic loading, either using laboratory X-ray sources or synchrotron radiation. We are developing a novel experimental setup based on a compact High Pulsed Power generator capable of producing intense X radiation through an X-pinch X-ray source. This source is specifically designed for time-resolved X-ray diffraction in Bragg geometry on gas gun experiments. Promising preliminary diffraction data obtained under static conditions are presented.

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