Post-shot analysis of targets designed to achieve a diagnosible compression of DT gas to 2. g/cm/sup 3/ or 10 x liquid density is reported. The SHIVA laser provided 15 to 20 TW of 1.06 ..mu..m laser light. Detailed comparisons of diagnostic results with hydro-code calculations are made. Implications for laser light absorption/scattering, thermal conduction, suprathermal electron preheat, implosion symmetry, and pusher-fuel mix are discussed. Uncertainties of the density determination methods are analyzed. Good overall consistency is found, indicating strong support for the successful attainment of 1.-3. g/cm/sup 3/.

The beam-target interaction in heavy ion fusion is theoretically understood, but experimental verification at appropriate beam intensities is not possible using existing accelerators. If fusion-intensity ion beams were to lose significantly less energy in passing through matter than calculated it would increase the cost of heavy ion fusion. In the worst case the cost scaling is such that a 25% decrease in energy loss would increase the cost of the accelerator by roughly 10%. In this paper we show that fundamental considerations place a lower bound on ion energy loss. The lower bound is not significantly less than the expected energy loss obtained from detailed calculations.

Materials accounting for special nuclear material in future fuel cycle facilities will draw heavily on sophisticated data-analysis techniques. Decision analysis, which combines elements of estimation theory, decision theory, and systems analysis, can be used to reduce errors caused by subjective data evaluation and to condense large collections of data to a smaller set of more descriptive statistics. The methods and requirements of decision analysis are discussed and illustrated by a conceptual design example of an advanced materials accounting system for a plutonium nitrate-to-oxide conversion facility.

The application of high-power lasers to production of extreme high pressures is discussed. Shock velocities consistent with pressures up to 2 TPa in aluminum have already been measured, and experiments in the 4 TPa range are now planned. We describe the status of our programs to develop new diagnostic techniques and perform experiments to characterize perturbing influences on the shock.

Laser fusion targets can produce implosions with a delay between the peak compression (neutron emission) and the laser pulse on the order of 0.2 to 2.5 ns. We use a fast detector system to measure x-ray and D-T neutron emission times with a resolution of 100 to 200 ps. An NE111 fluor (quenched with 2% benzophenone) coupled to a microchannel plate photomultiplier tube detects the arrival of neutrons and x rays. A separate biplanar vacuum photodiode detects the arrival of unabsorbed laser light scattered from the target. These signals are mixed, then recorded on a 500 MHz transient digitizer. The discussion includes a description of the time interval system, experimental data, data analysis techniques, and system calibration.

A subcommittee of the American Crystallographic Association (ACA) was formed to recommend some guidelines that would improve the overall quality of published powder diffraction data. An analysis of the Powder Diffraction File shows that many of the well-known techniques for obtaining good quality data are often not being applied, and hence there is a need for the establishment of publication standards. A major recommendation from this subcommittee is the use of a standard data-form at the author/referee level of publication. The proposed data-form is divided into five sections: sample characterizaton, technique, unit cell data, references, and the powder data. The information asked for in these five sections represents what, in most cases, the referee and editor can reasonably expect of experimenters seeking to publish their powder data. An example of a filled-out form is shown, and instructions for completing the form are given. Another recommendation is that the ACA request that the International Union of Crystallography consider implementing these recommendations in all IUCr journals.