MEASUREMENT OF K-SHELL FLUORESCENCE YIELD OF SOME ELEMENTS IN THE ATOMIC RANGE 5-LESS-THAN-OR-EQUAL-TO-Z-LESS-THAN-OR-EQUAL-TO-62 USING PHOTOIONIZATION

K shell fluorescence yields were measured for seven elements, Cs, Ba, La Ce,Pr, Nd and Sm, using a Ge(Li) detector. The targets were excited using 59.5 keV gamma rays from an Am-241 radioactive source of streng th 100 mCi. The obtained results were compared with the theoretical va lues and other measured values. The present results are in good agreem ent with earlier experimental and theoretical results.