F-64 L Shell X-ray Fluorescence Cross-Sections for Elements with 33 ≤ Z ≤ 50

Abstract

Accurate experimental data regarding the X-ray fluorescence (XRF) cross sections and fluorescence yields are important in basic studies of nuclear and atomic processes leading to the emission of X-ray and Auger electrons. The data is also required for many practical applications like elemental analysis by x-ray emission technique, dosimetric computation for medical physics and irradiation processes [1]. A systematic study of the Li (i =1-3) subshell x-ray fluorescence cross sections at the 5.89 keV photon energy has been undertaken for the elements in the atomic region 33  Z  50. The measurements have been performed under vacuum ~10 -2 torr using energy-dispersive spectrometer involving an LEGe (FWHM 150 eV at 5.895 keV) detector. The cross sections for the possible resolved L x-ray components were deduced and compared with those evaluated using the most reliable theoretical values of Li (i = 1, 2, 3) subshell photoionization cross sections, fluorescence yields, x-ray emission rates and Coster-Kronig transition probabilities [2]. For the L, L and L1,5 groups of x rays, the measured cross sections for all the elements are in agreement with theoretical cross sections. The measured L2,3 cross sections in the atomic region 39  Z  46 are in general agreement within ~10% except for 39Y, where the difference ~25% was observed. The comparison provides the insight regarding the cutoff energy of the L1-L2M4,5 and L1-L3M4,5 CK transitions at Z~39, and L1-L3M4,5 and L2-L3M4,5 CK transitions at Z ~50 as predicted by the RDHS model [2].