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The velocities and temperatures of shock waves generated by laser-driven hohlraum radiation fields have been measured for several indirect-drive inertial confinement fusion capsule ablator materials. For the first time, a time-resolved measurement of the preheat temperature ahead of the shock front has been performed and included in the analysis. It is found that preheat ahead of the shock front can cause significant shock propagation variations in the ignition capsule ablator materials being considered for the National Ignition Facility (NIF). If unaccounted for, these preheat effects could potentially preclude ignition at the NIF.

A central feature of an inertial fusion energy (IFE) power plant is a target that has been compressed and heated to fusion conditions by the energy input of the driver. This is true whether the driver is a laser system, heavy ion beams or Z-pinch system. The IFE target fabrication, injection and tracking programmes are focusing on methods that will scale to mass production. We are working closely with target designers, and power plant systems specialists, to make specifications and material selections that will satisfy a wide range of required and desirable target characteristics. One-of-a-kind capsules produced for today's inertial confinement fusion experiments are estimated to cost about US$2500 each. Design studies of cost-effective power production from laser and heavy-ion driven IFE have suggested a cost goal of about $0.25-0.30 for each injected target (corresponding to ∼10% of the 'electricity value' in a target). While a four orders of magnitude cost reduction may seem at first to be nearly impossible, there are many factors that suggest this is achievable. This paper summarizes the design, specifications, requirements and proposed manufacturing processes for the future for laser fusion, heavy ion fusion and Z-pinch driven targets. These target manufacturing processes have been developed-and are proposed-based on the unique materials science and technology programmes that are ongoing for each of the target concepts. We describe the paradigm shifts in target manufacturing methodologies that will be needed to achieve orders of magnitude reductions in target costs, and summarize the results of 'nth-of-a-kind' plant layouts and cost estimates for future IFE power plant fuelling. These engineering studies estimate the cost of the target supply in a fusion economy, and show that costs are within the range of commercial feasibility for electricity production.

Seabed characterization and model based processing: Past, present, and future.Tritium handling equipment and methods at the Savannah River Site Tritium Facilities have been continually improved since tritium processing operations began in 1955. Several new technologies were introduced into the Tritium Facilities in the 1980's. One of these is the use of fiuidless, mechanical pumps (N ormetex and Metal Bellows) to replace mercury pumps. A second is the use of metal hydride technology to store, purify, isotopically separate, pump, and compress hydrogen isotopes. Metal hydrides, such as La-Ni-AI alloys and Pd loaded on kieselguhr, offer significant flexibility and size advantages compared with conventional tritium handling technology, such as gas tanks, thermal diffusion columns, and mechanical compressors. Metal hydrides have been used in the Tritium Facilities since 1984 with the most important application of this technology being planned for the Replacement Tritium Facility, a $140 million facility scheduled for completion in 1990 and startup in 1991.