Iron Opacity Platform Performance Characterization at the National Ignition Facility

A high temperature opacity platform has been fielded at the National Ignition Facility (NIF). The platform will be used to study opacity in iron at a temperature of \textasciitilde 160 eV. The platform uses a \textasciitilde 6 mm diameter hohlraum driven by 128 laser beams with 530 kJ of energy in a \textasciitilde 3 ns pulse to heat an iron sample. Absorption spectra of the heated sample are generated with a broadband pulsed X-ray backlighter produced by imploding a vacuum-filled CH shell. The shell is 2~mm in diameter and \textasciitilde 20 microns thick, driven by 64 beams with 250 kJ in a 2.5 ns pulse. The hohlraum and backlighter performance have both been investigated recently and will be discussed in this presentation. * This work was performed by National Security Technologies, LLC, under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy. DOE/NV/25946--2892.