Measurements of L 1 , Lα, Lβ and Lγ x‐ray fluorescence cross‐sections in heavy elements excited by 36.62, 43.69, 48.30, 50.20 and 53.50 keV photons

L 1 , Lα, Lβ and Lγ x‐ray fluorescence cross‐sections were measured in Au and Pb at excitation energies of 36.62, 43.69, 48.30, 50.20 and 53.50 keV. Measurements were made using an x‐ray tube with a secondary exciter system as the excitation source. 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 L x‐ray fluorescence cross‐sections even for low‐intensity x‐rays (L 1 ). The experimental results were compared with the theoretically calculated values of L x‐ray fluorescence cross‐sections and a fairly good correspondence was observed.