A novel method for measuring K-shell photoelectric parameters of high-Z elements

Abstract

The K-shell jump ratio, jump factor and the ratio of total to K-shell photoelectric cross section at K edge have been determined for Hf, Ta, Au and Pb by adopting a novel method. In this method, continuous external bremsstrahlung (EB) photons are produced in a thin nickel elemental converter by beta particles from a 90Sr–90Y weak beta source. The spectrum of EB photons transmitted through the elemental targets of Hf, Ta, Au and Pb is recorded with an HPGe detector coupled to an 8K multichannel analyser. The transmitted spectrum shows a sharp decrease in intensity at the K-shell binding energy of the target atom. The region of sharp decrease is fitted to a sigmoidal function and the K-shell jump ratio, jump factor and the ratio of total to the K-shell photoelectric cross section at K edge are determined. The measured values are compared with the theoretical values.