Systematic measurements of M X‐ray components X‐ray fluorescence cross‐sections for the elements with 77 ≤ Z ≤ 92 by employing laboratory source based energy dispersive X‐ray fluorescence setup

The differential X-ray fluorescence (XRF) cross-sections for (M xi(2), M xi(1), M delta(1)), (M delta(2), M alpha(1,2) M-5-O-3), (M beta, M-4-O-2,O-3), (M gamma, Mm(2), M-3-N-4, M-5-O-2,O-3), (Mm(1), M-3-N-6,N-7, M-3-O-4,O-5) and (Mm(2), M-2-N-6) group of M X-rays components have been measured for the elements with 77 <= Z <= 92 following photoionization by Mn K X-rays (EK alpha beta = 5.96 keV) obtained from Fe-55 radioisotope. The measurements were performed in annular source geometry at 126 degrees emission angle using a low-energy Ge (LEGe) detector. The measured cross-section values are compared with theoretical values calculated using available sets of M-i (i = 1-5) photoionization cross-sections, radiative emission rates WO, Coster-Kronig (f(ij)), and fluorescence (omega(i)) yields. The measured XRF cross-sections for the (M xi(2), M xi(1), M delta(1)), (Mm(1), M-3-N-6,N-7) and (Mm(2), M-2-N-6) groups of X-rays agree with the theoretical values within the experimental errors. The (M beta, M-4-O-2,O-3) group of X-rays exhibit agreement with theoretical values within experimental uncertainty for all the elements under investigation except Au-79 and Hg-80. The XRF cross-section for the (M delta(2), M alpha(1,2)) group of X-rays are in general higher by similar to 20% for the elements with Z = 77-83 and exhibit agreement for the Th-90 and( 92)U elements. For the (M gamma, Mm(2), M-3-N-4) X-ray group, the measured values are generally higher than the theoretical values, but the deviations are within experimental uncertainties. The large deviation in measured XRF cross-section for different M X-ray components from the theoretical ones are attributed to (i) poor separation of M X-ray components (ii) contribution of self-resonant Raman scattering (RRS) process and (iii) self-fluorescence of M-5 subshell by M-i subshell X-rays (i = 1-3).