Radiative heating of plastic-tamped aluminum foil by x rays from a foam-buffered hohlraum

The time dependence of the x-ray absorption of aluminum samples heated with intense radiation sources from a foam-buffered gold hohlraum has been studied in this work. Hydrodynamic simulations were used to illustrate the plasma conditions in the plastic-tamped aluminum foils contained in this type of hohlraum. Experiments were conducted to measure the K-shell x-ray absorption spectra of the aluminum sample. With densities taken from the hydrodynamic simulations, electron temperatures were then inferred by fitting the measured absorption spectra with detailed-term-accounting calculations. The inferred temperatures have a maximum of about 93 eV and were found to agree within 25% with the simulated results at times after 1 ns, indicating that the use of foam shields, together with a compact cavity, has created a clean and high-temperature radiation source preferable to opacity measurements.