Total K fluorescence yields for Fe, Cu, Zn, Ge and Mo

Total K fluorescence yields were determined for five low Z elements Fe, Cu, Zn, Ge and Mo using reflection geometry and employing a Xe filled proportional counter having a 5 mil (1.27*10 -2 cm) Be window. The targets were photoexcited using 59.5 keV soft gamma rays as primary radiation from an 241 Am radioactive source of strength 300 mCi. An effective graded shielding arrangement was used to minimize the background radiation and multiple scattering. Elemental foils of uniform thickness and purity better than 99.5% were used as targets. The fluorescence spectra were recorded in a 1 k multichannel analyser. The data was carefully analysed and total K fluorescence yields were determined. The results obtained were 0.350, 0.425, 0.471, 0.538 and 0.758 for Fe, Cu, Zn, Ge and Mo respectively. The experimental results are compared with theoretical predictions, semiempirical estimates and also earlier results obtained by other methods.