Reactivity measurements of various target elements

The amount of enriched uranium to support various type of target elements was determined in the Hanford Test Reactor. This report describes the measurement of separate and striped loadings for canned thorium oxide, bismuth, lithium-aluminum, and, in addition, bare depleted uranium. This experiment was undertaken to provide information needed to estimate the E-metal requirements in a production reactor when replacing natural uranium with target material. The amount of enriched uranium which is required to maintain the reactivity in support of target materials must be known to properly predict total reactor reactivity. Danger coefficient measurements were made during original startup tests to provide this information. However, fuel dimensions have changed and new target materials have been introduced which have not been tested in this manner. The target of particular interest at this time of thorium oxide.