Analysis of radiation-driven explosive flyers

There is great interest in being able to use the x-ray output from a Z-pinch for equation of state measurements at extreme conditions. However, the direct x-ray output from the pinch produces a very sharp and rapidly attenuating pressure pulse in target materials. To obtain high quality measurements with this source, a mechanism for generating non-attenuating waves is needed. One possibility involves using the x-ray source to throw a near-normal density intermediate driver at the target, a situation similar to more conventional configurations. To scope out preliminary design parameters, we used the ALEGRA code to simulate a number of different possibilities involving the driver and the gap between it and the target. We used a somewhat idealized radiation source-a main x-ray pulse 30 ns long at its base and peaking at a blackbody temperature of 100 eV. The calculations suggest that a 100-micron aluminum driver with a 90-micron gap will yield a 15-ns-wide non-attenuating pulse with an amplitude of over 250 GPa.