抄録
Lead-Bismuth-Eutectic (LBE) has good characteristics as a nuclear reactor coolant, but it also has a problem of polonium production. The research for polonium contamination is necessary for utilization of LBE in nuclear reactor. Baking method in vacuum for polonium removal from contaminated material surface and unfolding method for calculation of polonium distribution in depth of irradiated LBE ingot were investigated. The baking experiment was performed to the quartz glass palates contaminated by polonium in vacuum, and the results indicated that baking method (over 300℃) was so effective for the removal of polonium from the quartz glass plate. And, the alpha ray spectrum was measured from the surface of irradiated LBE ingot. From measured spectrum, the polonium distribution in depth of irradiated LBE ingot was calculated by a quadratic programming unfolding code.
