Hohlraum X-ray deposition in indirect-drive ICF ablator materials

Accurate measurements of shock timing and ablator x-ray burnthrough will be essential for the successful ignition of an indirect-drive inertial confinement fusion (ICF) capsule. In previous work [1], measurements of ablator shock velocities, shock temperatures, and preheat temperatures were made using a 280 nm Streaked Optical Pyrometer (SOP) [2]. The x-ray fluxes were supplied by hohlraums driven by the University of Rochester Omega Laser [3]. More recent ablator experiments at Omega have extended the previous work by using an absolutely calibrated 600-800 nm SOP [4] together with a line-imaging velocity interferometer [5] similar to the diagnostic proposed for accurate National Ignition Facility (NIF) ignition shock timing measurements [6]. Important new information has been obtained relating to ablator surface movement prior to shock breakout, ablator preheat temperature, and preheat effects on the anvil and window components of the shock timing diagnostic system

Studies of Dynamic Properties of Shock Compressed FCC Crystals by in Situ Dynamic X-Ray Diffraction

There were 5 laser experiments conducted to date in FY-01 under the ongoing project to study the response of single crystal fcc materials under shock compression. An additional 10 laser shots are planned for August, 2001. This work has focused on developing capability to record diffraction from multiple lattice planes during the passage of a shock through a thin foil of single crystal copper, while simultaneously performing separate shock sample recovery experiments to study the residual deformation structure in the recovered samples