Development of 3D-scan-based efficiency calibration method of complex-shaped materials in gamma spectrometry

Abstract

To address gamma spectrometry on complex-shaped materials when the conventional method based on certified reference materials is impractical, we propose a new 3D-scan-based source modeling method for reflecting geometry of complex-shaped materials. Various complex-shaped materials were selected, scanned with tailored methods depending on the scanned objects, and the scanned 3D data were integrated into the source term models for Monte Carlo simulation. The developed method has been confirmed that all complex-shaped materials thus created can be cast into the Monte Carlo simulation toolkit Geant4 as source terms. It produced mesh deviations of all samples within 1 mm, validating its utility for practical applications. The developed method was experimentally validated using CRM, proving the accuracy of the method. The proposed method enables a comprehensive efficiency calibration for radioactivity analysis of complex-shaped materials without the need for destructive preprocessing.