L X-RAY-FLUORESCENCE CROSS-SECTIONS AND INTENSITY RATIOS IN SOME HIGH-Z ELEMENTS EXCITED BY 23.62-KEV AND 24.68-KEV PHOTONS

Ll, Lalpha, Lbeta, and Lgamma x-ray fluorescence cross sections have been measured for the elements Pr, Ho, Yb, Au, and Pb using photon energies of 23.62 and 24.68 keV. Measurements have been performed using an x-ray tube with a secondary-exciter system as the excitation source. The secondary exciters of Cd and In were pure metals (> 99.9%). The x-ray tube with a secondary-target arrangement was used to obtain high intensity with a high degree of monochromatization. By using an x-ray tube, it is possible to measure x-ray fluorescence cross sections and ratios even for low-intensity x rays (Ll). Experimental results have been compared with the theoretically calculated values of L x-ray fluoresence cross sections. A fairly good correspondence is observed between experimental and calculated values. The intensity ratios for the intense transitions I(Lbeta)/I(Lalpha) are in good agreement with the calculated values.