Supersonic jet experiments on Sandia National Laboratories' Z accelerator*

An x-ray-driven supersonic jet experiment has been performed on Sandia National Laboratories' Z accelerator. ~The 130-140 eV drive of a z-pinch-driven hohlraum ablates a cylindrical Al pin (300-micron-length, 600-micron-diameter) that is embedded half way into a 150-micron-thick Au washer. ~A strong convergent shock is formed on axis, and the dense Al plasma propagates into a 300 mg/cc RF foam, on the opposite side, and a jet is formed. ~The jet evolution is imaged by a 6.151 keV curved-crystal imaging system with 10-11 micron spatial resolution. ~This allows the bow shock, Kelvin-Helmholtz roll-up, and other jet features to be studied in detail and then compared with various radiation hydrodynamics codes. ~Radiographs can be reduced to running integral ``1-T'' plots (T=6.151 keV transmission) through various sections (of chosen width) of the jet along the direction parallel to the foam's z-axis, to provide metrics for direct comparison with simulations. Results are presented in this and the following paper.