Fuel content characterization and pressure retention measurements of DT-filled laser fusion microballoon targets

We have developed a nondestructive assay of the fule content of deuterium-tritium (DT) -filled microballoon laser fusion targets, which is based on β-particle counting rates. Using a model employing transmission measurements of kilovolt electrons through thin films, observed count rates are correlated with the amount of tritium in the glass walls and hollow interior of the microballoons. It has been shown that gas pressure in balloons can be calculated from tritium content and a knowledge of the initial gas composition since D and T were found to leak at the same rate. This assay technique is primarily applicable for balloons with glass wall thicknesses