Simulated mixed absorbers and effective atomic numbers for γ attenuation

The total γ-ray interaction cross-sections on mixed absorbers were determined at 662 keV with a view to study the effective atomic numbers for γ-ray absorption under narrow beam good geometry set-up. The measurements were taken for the combination of metallic absorbers like aluminium, copper, lead and mercury and also for the simulated absorbers by rotating the targets. ORTEC HPGe and NaI(Tl) detectors were used for detection of γ-rays. The experimental results compare favourably with theoretical values derived from XCOM package and suggest the usefulness of the concept of effective atomic numbers and the utility of the rotating absorbers technique.