APL007-2-7 Calculation of Mass Attenuation Coefficients and Cross Sections for Different Elemental Metals

Abstract

The Compton effect is studied with the measurement of a γ-ray energy spectrum using a scintillator, photomultiplier tube, and multichannel analyzer. The gamma rays interact with the detector, producing all three primary interaction processes, so that every phenomenon that is being studied in a sample is also taking place in the detector itself along with several other effects that mask the process of interest. The linear and mass attenuation coefficients are studied for the elements Ni, W, and Al and materials at different photon energies using a continuous spectrum from the ¹³⁷Cs source via standard collimated beam shielding. The linear and mass attenuation coefficients calculated with the win X-COM program are in good agreement with the theoretical values. That the materials with high photon absorption cross-section may be used for changing the shape of the radiation spectrum. The increase in their thickness decreases the mass attenuation coefficient. The measurements were carried out using a 3"×3" NaI (Tl) detector system and an 8 mCi Cs-137 source.