Elastic scattering of $\sf{59.54}$ -keV $\sf{\gamma}$ -rays in elements with $\sf{22 \leq {Z} \leq {92}}$ at momentum transfer $\sf{0.4 \leq {x} \leq 4.7~{\AA}^{\sf -1}}$

Abstract

Differential cross sections for elastic scattering of the 59.54 keV γ-rays in elements with 22 ≤Z ≤92 have been measured over the angular range 10○–160○corresponding to the momentum transfer 0.4 ≤x ≤4.7 A-1. The measurements at forward and backward angles were performed using the 241Am radioactive point-source, target and the Ge detectors in the transmission and reflection arrangements, respectively. The measured differential scattering cross sections are compared with those based on the form-factor (FF) formalism and state-of-the-art S-matrix calculations to differentiate between their relative efficacies and to check angular-dependence of the anomalous scattering factors (ASF) incorporated as correction to the modified form-factor (MF). The S-matrix values exhibit agreement with the measured data at backward angles and differences ∼10% at forward angles. The scattering cross sections based on the MF including ASF’s are in general lower at various angles by up to 20% for medium- and high-Z elements. The observed deviations being higher at the forward angles infer possibility of angular-dependence of ASF’s.