Measurement of L Shell X-Ray Production and Average L Shell Fluorescence Yields for Some Heavy Elements at 123.6 keV

The $L_{3l},$ $L_{3α},$ $L_{3β},$ $L_{2β},$ $L_{2γ},$ $L_{2η},$ $L_{1β}$ and $L_{1γ}$ X-ray production cross-sections and L shell average fluorescence yields were measured for the elements from Re to U using excitation energy of 123.6 keV. Measurements were performed using an $\text{}^{57}Co$ annular radioactive source and a Si(Li) detector. The theoretical values of the cross-sections were calculated using theoretically tabulated values of subshell photoionization cross-sections;the Coster-Kronig transition probabilities were based on the Dirac-Hartree-Slater theory and radiative emission rates. Experimental results were compared with the theoretically calculated values of L shell X-ray cross-sections. The present experimental results are in agreement with theoretical values.