Microdosimetry studies of plutonium oxides

NUCL 46

Lav Tandon1, Alice K. Slemmons1, John Blackadar1, Jay A. LaVerne2, John D. Robertson3, Jeffrey Schwarz4, Anthony J. Sanchez1, and David E. Hobart1. (1) Chemistry Division, Los Alamos National Laboratory, Mail Stop G740, Los Alamos, NM 87545, (2) Notre Dame Radiation Laboratory, University of Notre Dame, (3) Department of Chemistry, University of Missouri, (4) Department of Chemistry, University of Kentucky
Important issues surrounding long-term storage of plutonium are corrosion and gas generation that lead to ultimate failure of the stainless steel containers. The chemical reactions used to model these radiolytic effects depend upon the dose (energy) escaping from these materials. An important variable in calculating and modeling these effects is the physical particle size of the plutonium oxide. The average alpha particle energy and dose emitted by varying particle size fractions of PuO2 has been studied experimentally in the present work and will be presented. Alpha spectrometry, ionization chamber counting, and gamma spectroscopy are being used to measure the alpha energy, total energy, and isotopic composition of the materials. The present results are novel because the dose fraction actually emitted by the various particle sizes has previously only been predicted, based on spherical models, rather than actually determined experimentally. Comparisons of experimental data with these physical models will be discussed.