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High-Z metallic foils including rare-earth (RE) elements are required for some experiments implemented on the Laser Megajoule. A specific process based on physical vapor deposition and laser machining was developed to produce high-Z material foils meeting strict specifications. This process allows pure metallic ultrathin foil fabrication from a few hundred nanometers to several microns of thickness of any high-Z materials. In the case of RE metals sensitive to oxidation, thin foils are buried under aluminum protective layers of about a few hundred nanometers. These metallic thin foils are flat, show thickness uniformity over 95%/cm2, and have roughness of about 10 nm. The foils are opaque to light, have a density similar to bulk material, present an oxygen content of about 1 at. %, and are stable over months under atmospheric conditions.

Hydrodynamics growth experiments involve rippled ablator samples (CHx, Ge:CH, or Si:CH). The rippled surface features a microscale mathematical shape (sinusoidal functions are widely used). Neverth...

The cryogenic target assemblies (CTAs) designed for Laser Megajoule (LMJ) experiments have many functions and have to meet severe specifications imposed by implosion physics, the CTA thermal environment, and the CTA interfaces with the Megajoule laser cryogenic target positioner. Therefore, CTA fabrication uses many challenging materials and requires several technological studies. During the last 2 years, many developments have enabled better collection of comprehensive data on target constitutive materials and improvements in the fabrication of the CTA base, hohlraum, and aluminum turret.Studies have been carried out (a) to better characterize thermal properties of materials allowing optimization of the thermal simulation of the hohlraum, (b) to improve the CTA base fabrication process in order to optimize thermal studies of the LMJ experimental filling station (EFS), and (c) to determine coatings on the polyimide membrane that may limit the 300 K thermal effect on the microshell and increase the...