Study of Transmission and Scattering of Gamma-Rays Through Some Materials

Abstract

Mass attenuation coefficients t/p (cm2 I g) of some compounds and elements have been very accurately measured by using an extremely-narrow-collimated­ beam transmission method. The effect of absorber position, collimation solid angle and the sample thickness on the measured mass attenuation coefficient at three different gamma ray energies ( 59.54, 661.6 and 1332.5 keV ), have been studied. Mass attenuation coefficients, effective atomic numbers, electron densities

and total atomic cross sections for some HC (Hydrogen-Carbon), HCO (Hydrogen-Carbon-Oxygen) and HCON (Hydrogen-Carbon- Oxygen-Nitrogen) compounds (with different Hydrogen weight fraction F11 ) have been measured. The experimental results of the mass attenuation coefficients are in agreement

with the the theoretically calculated values. A linear relation between the mass attenuation coefficient and F,, (the hydrogen weight fraction) in HC compounds was obtained. From this relation the hydrogen weight fraction of paraffin wax was determined as 20.11 % and its effective molecular structure can be written as ( C2 H6 ). • Absolute values of coherent plus incoherent differential scattering cross sections of the 59.54 keV gamma ray of 241Am from Anthracene, POPOP, Polystyrene and Paraffin were experimentally determined for ten scattering angles between 30° and 120°. The corresponding theoretical differential cross sections were calculated by means of form factors and incoherent scattering functions.