Experiments conducted on the LANL Trident two-beam facility show the viability of fluorescence-based imaging as a diagnostic in high-energy-density (HED) hydrodynamics experiments. Passive fluorescence experiments using titanium-pumped scandium-oxide, or iron-pumped manganese-oxide, show that fluorescence emission can be produced at sufficient intensities to be useful. Dynamic experiments, designed to demonstrate particle tracking in time for particle imaging velocimetry (PIV), were marginally successful in that only very large particulates could be definitively observed. However, our results indicate that experiments conducted on facilities offering a greater energy would be less susceptible to the limitations confronted in this study and thus, significantly enhance the prospect of PIV as an effective diagnostic tool in HED experiments.

Measurements of Ti He-like x-ray emission (4.75 keV) from solid targets irradiated with nanosecond pulses on the TRIDENT laser facility are examined. Relative x-ray emission and conversion efficiency was measured as a function of laser irradiance conditions using a crystal spectrometer and step-filtered charge coupled device and x-ray film. Data on the x-ray emission with and without random phase plates is presented. Difficulties and caveats in the diagnostic techniques are also presented. Analysis of step-filtered data suggests a high-energy x-ray tail.

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100–300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 μm spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV.

One of the difficulties in developing accurate numerical models of radiation flow in a coupled radiation-hydrodynamics setting is accurately modeling the transmission across a boundary layer. The COAX experiment is a platform design to test this transmission including standard radiograph and flux diagnostics as well as a temperature diagnostic measuring the population of excitation levels and ionization states of a dopant embedded within the target material. Using a broad range of simulations, we study the experimental errors in this temperature diagnostic. We conclude with proposed physics experiments that show features that are much stronger than the experimental errors and provide the means to study transport models.

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