Parametrization of the total photon mass attenuation coefficients for photon energies between 100 eV and 1000 MeV

Abstract

A convenient way of generating mass attenuation coefficients for data analysis in various fields of X-ray spectroscopy is by means of semi-empirical schemes. However, the validity of most of the existing schemes is limited to relatively narrow energy intervals (typically 1-50 keV) and their accuracy is usually poor especially in regions near absorption edges. A few years ago, we use a new semi-empirical scheme that enabled us to fit, for the first time, photon data for all elements in the very wide energy range, i.e. between 0.1 and 1000 keV. The scheme was found flexible enough to provide excellent fit to the most recent compiled photon cross section data in the entire energy range. It was based on fitting data to an exponential function with the addition of a Klein-Nishina term to account for dominant incoherent scattering at higher energies. In the present work, our former scheme is extended beyond the pair-production threshold (1.02 MeV) all the way to 1000 MeV. An interactive MS Windows based computer program for generating, printing and displaying mass attenuation coefficients based on the proposed scheme has been developed.