Feasibility of measuring ionic diffusion in x-ray heated foils using x-ray radiography on Z

Ionic diffusion is the process by which ions of different species traverse an initial interface. In moderate to strongly coupled plasmas this process can be stronger than expected by classical arguments, leading to more efficient mixing. We present measurements of this process taken using a novel platform on Z where a bright x-ray source is used to heat a sample comprised of repeating low-Z/high-Z interfaces. X-ray radiography is used to measure the change in the spread of the edge created by the interface as a function of time. Our results show that it should be possible to measure this phenomenon with existing capabilities and provide constraining data, though better characterization of the drive and sample conditions are needed for quantitative comparisons.