The Development of a CdWO4-Based Inorganic Scintillation Detector for Neutron Detection in Radiological Applications

Abstract

This project aimed to evaluate CdWO₄ as a scintillation detector for neutron detection and to assess its ability to distinguish neutron interactions from gamma background for use in radiation protection. The detector was assembled with a PMT and tested with Cs-137, Am-Be sources, and absorber materials. Cs-137 calibration showed that a shaping time of 3 µs gave the best gamma resolution of about 9% at 662 keV. While neutron runs required a shaping time of 10 µs to capture the slow light output, although this reduced the resolution. Lead-only baseline runs confirmed that the spectra were gamma dominated. The addition of cadmium and gadolinium absorbers produced no clear suppression, as their effects were masked by scattering in the water tank and the experimental geometry. A peak consistent with neutron capture was observed during neutron runs, but its exact origin could not be confirmed due to shielding and scattering. The results demonstrate that CdWO₄ is a stable and practical scintillator with measurable neutron response, but limitations such as absorber placement, geometry, scattering, and the long decay time restricted its ability to separate neutron and gamma signals. Future work should optimise absorber positioning, improve collimation and moderation, reduce gamma background, and employ simulation studies to model the detector response.