Evaluating laser-driven Bremsstrahlung radiation sources for imaging and analysis of nuclear waste packages.

A small scale sample nuclear waste package, consisting of a 28mm diameter uranium penny encased in grout, was imaged by absorption contrast radiography using a single pulse exposure from an X-ray source driven by a high-power laser. The Vulcan laser was used to deliver a focused pulse of photons to a tantalum foil, in order to generate a bright burst of highly penetrating X-rays (with energy >500keV), with a source size of <0.5mm.

Double slit interferometry to measure the EUV refractive indices of solids using high harmonics.

Accurate values of the extreme ultraviolet (EUV) optical properties of materials are required to make EUV optics such as filters and multilayer mirrors. The optical properties of aluminum studied in this report are required, in particular, as aluminum is used as an EUV filter material. The complex refractive index of solid aluminum and the imaginary part of the refractive index of solid iron between 17 eV and 39 eV have been measured using EUV harmonics produced from an 800 nm laser focused to 10(14) Wcm(2) in an argon gas jet impinging on a double slit interferometer.