Measurements of elastic scattering cross sections for 25.2, 28.5, 37.4, 36.8, and 42.2 keV X‐ray photons in elements with 22 ≤ Z ≤ 83

Abstract

The differential elastic scattering cross sections were measured for 25.2 (Sn‐Kα), 28.5 (Sn‐Kβ1,3), 37.4 (Nd‐Kα1), 36.8 (Nd‐Kα2), and 42.2 (Nd‐Kα1,3) keV X‐ray photons at 139° scattering angle in elements with 22 ≤ Z ≤ 83. The measurement was done in reflection mode experimental setup involving 50Sn/60Nd secondary targets excited with 241Am radioisotope. The scattered X‐ray photons were detected using a high‐resolution low energy germanium detector (horizontal configuration, FWHM = 300 eV at 59.5 keV) coupled with computerized multichannel analyzer. The intensity of X‐ray photons along with geometrical factors were calculated from the theoretical knowledge of K X‐ray fluorescence cross sections and measured K X‐ray yields from excited targets. The measured values of differential cross sections were compared with the theoretical available values based on form factor and second‐order S‐matrix (SM) approaches. The experimental values of cross sections exhibit a large deviation from modified form (MF) values for the elements with BK/Ein ≈1, where BK is the K‐shell binding energy of electrons and Ein is the energy of incident photon. These deviations in experiment results were smooth out by the inclusion of anomalous scattering factors (ASFs) to the MF values. The measured elastic cross sections were found to be ~7% lower than MFASF values and agree with SM values for all elements under investigation.