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Experiments on the Z accelerator have demonstrated the ability to produce warm dense matter (WDM) states with unprecedented uniformity, duration, and size. Significant progress to combine x-ray Thomson scattering (XRTS), a powerful diagnostic for WDM, with the unique environments created at Z has been accomplished. The large current of Z is used to magnetically launch Al flyers to impact CH₂ foam (0.12 g/cm³) samples. The uniformly-shocked CH₂ foam volume is about 10 mm³ and the steady shock state lasts up to about 100 ns, which are approximately 1000 & 100 times larger, respectively, than typical laser shocked samples. The Z-Beamlet laser irradiates a 5 μm thick Mn foil near the load to generate 6.181 keV Mn-He-α x-rays that penetrate into the CH₂ foam and scatter from it. A high sensitivity x-ray scattering spherical spectrometer with both high spatial and spectral resolution is fielded, which enables benchmark quality data by simultaneously measuring x-rays scattered from shocked and ambient regions of the CH₂ foam, and the Mn x-ray source. Experimental efforts have achieved low x-ray background and mitigation of load debris, and measured high quality XRTS data of ambient CH₂ foam have validated the technique.

In order to take advantage of geometrical convergence, we investigated a method, where a beryllium liner drives a cylindrical shockless compression in a cryogenic deuterium fill. The metal liner acts as a current carrier as well as a pressure boundary to the fill. The required driving pressure was obtained through a fictitious flow (FF) simulation [D S Clark and M Tabak 2007 Nucl. Fusion47 1147]. A current model that can recreate the FF compression inside the liner by shaping the current pulse, is then introduced. This method also allows efficient compression of hydrogen at low entropy, enabling the recreation of conditions present in the interior of gas giants and potentially the observation of a transition into a metallic state. Our two-dimensional simulations show that thick liners remain robust to magneto-Rayleigh-Taylor instability growth, suggesting that cylindrical isentropic ramp compression is a promising scheme for extending deuterium's experimentally measured equation of state.