Experiments on the Sandia Z pulsed-power accelerator have demonstrated the ability to produce warm dense matter (WDM) states with unprecedented uniformity, duration, and size, which are ideal for investigations of fundamental WDM properties. For the first time, space-resolved x-ray Thomson scattering (XRTS) spectra from shocked carbon foams were recorded on Z. The large (> 20 MA) electrical current produced by Z was used to launch Al flyer plates up to 25 km/s. The impact of the flyer plate on a CH 2 foam target produced a shocked state with an estimated pressure of 0.75 Mbar, density of 0.52 g/cm 3 , and temperature of 4.3 eV. Both unshocked and shocked portions of the foam target were probed with 6.2 keV x-rays produced by focusing the Z-Beamlet laser onto a nearby Mn foil. The data is composed of three spatially distinct spectra that were simultaneously captured with a single spectrometer with high spectral (4.8 eV) and spatial (190 m) resolutions. Detailed spectral information from three target locations is provided simultaneously: the incident x-ray source, the scattered signal from unshocked foam, and the scattered signal from shocked foam.

We report on direct, radiographic measurement of the stagnation phase of a magnetically driven liner implosion. The liner is filled with liquid deuterium and imploded to a minimum radius of 440 μm (radial convergence ratio of 7.7) over 300 ns, achieving a density of ≈10 g/cm3. The measured confinement time is ≈14 ns, compared to 16 ns from 1D simulations. A comparison of measured density profiles with 1D and 2D simulations shows a deviation in the reflected shock trajectory and the liner areal density. Additionally, the magneto Rayleigh-Taylor instability causes enhanced compression with shorter confinement in the bubble region compared to the spikes. These effects combine to reduce the pressure-confinement time product, Pτ, by 25% compared to the simulations.

Warm dense matter exists at the boundary between traditional condensed matter and plasma physics and poses significant challenges to theoretical understanding. It is also critical for applications, including z-pinch and inertial fusion laboratory experiments and in astrophysical objects such as white dwarfs and giant planet interiors. The modern generation of high energy density facilities has made it possible to create warm dense conditions in the laboratory. Creating warm dense matter is challenging, but thorough understanding also requires accurate detailed diagnostics. This report describes research aimed at combining x-ray Thomson scattering, a powerful diagnostic for warm dense matter, with extreme environments created at the Z facility. Significant advances in in-house Sandia capability have been achieved, including x-ray scattering theory, instrumentation, and experiment design, execution, and interpretation. This work has set the stage for novel x-ray scattering investigations of warm dense matter at the Z facility in the near future.4

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