On the investigation of Szilard-Chalmers effects in gold foils

Abstract

Preliminary experiments indicate the release of radiogold into an aqueous phase when gold foils that are submerged in water are irradiated with neutrons. Experiments verify this quantitively, as the yield in 198Au is ten-fold when gold foils are irradiated in H2O compared to removal of said foils from the aqueous phase after mechanical shaking and prior to irradiation. Further experiments detail that there is no correlation between the activity of the gold foils with the amount of radiogold being released from the foils. However, the duration of the neutron bombardment is a key factor in the ejection of 198Au into the aqueous phase, although the exact relationship between the duration of neutron irradiation and the yield of no-carrier-added 198Au is not fully known. Changing the matrix in which the neutron irradiation takes place from an aqueous to a solid phase, leads to surprising, yet not fully conclusive results, where more radiogold is released into the solid phase, compared to the aqueous phase. Finally, the crystallization experiment conducted for speciation shows that the investigated nuclear reaction produces 198Au3+.