Determination of impurity content in gold foils

The content of impurities in gold foils intended for neutron flux measurements has been determined. The gold foils were irradiated by a high neutron flux and the activities of the activated impurities were measured after a cooling period of 48 days by a HPGe spectrometer. The activated impurities were Zn and Ag, and their content was determined from the measured activities ratio of the isotopes 65Zn and 110mAg to 198Au. The activated isotopes have longer half-lives than 198Au and they could be measured after the cooling period.