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Low density polymer foams have been an integral part of targets used in Inertial Confinement Fusion (ICF) experiments. In order to accomplish this the formulation of the High Internal Phase Emulsion (HIPE) foam had to be optimized. Along with a change in density and the incorporation of fillers into a foam, there is also a change in the pore size and the distribution of pore sizes. The emulsion technique used to produce these foams is amenable to modification providing foams with a wide range of densities, 15 mg/cm3 to 500 mg/cm3, and metal loadings up to 90 percent by weight. A qualitative distribution of pore size can be seen visually with scanning electron microscopy (SEM). At low metal loadings SEM did not observe the submicron metal particles. The distribution of these particles in the foam matrix was seen with near-infrared imaging. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In high energy density laser experiments, targets often require small, low-density, foam components. However, their limited size can preclude single component characterization, forcing one to rely solely on less accurate bulk measurements. We have developed a monochromatic imaging system to characterize both the density and uniformity of single component low-mass foams. This x-ray assembly is capable of determining line-averaged density variations near the 1% level, and provides statistically identical results to those obtained at the Brookhaven's NSLS. This system has the added benefit of providing two-dimensional density data, allowing an assessment of density uniformity. [ABSTRACT FROM AUTHOR]