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

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.

X-ray mass attenuation coefficients and imaginary components of the atomic form factor of zinc over the energy range of 7.2–15.2 keV

“…The National Institute of Standards and Technology (NIST) currently supports two such tabulations; XCOM [11,12] and FFAST [13][14][15]. Significant differences exist in the values of the form factors from these tabulations across a wide range of energies and elements [13,16], the largest being at and immediately above absorption edges [17]. These discrepancies lead to a significant problem when calculating mass attenuation coefficients in these regions.…”

Measurement of the x-ray mass attenuation coefficients of gold in the38–50-keV energy range

“…Previous measurements were made using Bremsstrahlung radiation [14,15], but such studies have not had the accuracy or statistics to distinguish between different theoretical calculations.…”

The excitation probabilities of Kα,β and Lα1,2 for some elements in 56≤Z≤68 at 59.54keV

“…The Compton scattered gamma photons from a low atomic number elements are used in this method. The last method is the bremsstrahlung method (Nayak and Badiger, 2006;Hosur et al, 2011) based on continuous bremsstrahlung radiation from a weak beta source is allowed to fall on a thin target.…”