Measurements of EK-10 nuclear fuel by gamma scanning

The burnup of EK-10 nuclear fuel of the Iraqi research reactor was measured using the scanning technique. The fission fragment CS-137 was used as a monitor because of its long half-life. The total activity of CS-137 in a fuel cell was determined by measuring the activity at discrete levels along the spent fuel and by rotating the cell about its vertical axis at each discrete level. The measured values were then integrated numerically along the length of the active part of the fuel. The total activity of CS-137, the efficiency, and the data about the physical reactor, and fuel constants, and history of irradiation and cooling time are used in an expression to calculate the number of U-235 atoms fissioned and to estimate the fuel burnup. 30 tabs.; 20 figs.; 45 refs