Alpha-ray Imaging Measurement and Scintillation Properties of Cs3Cu2I5 Crystals

Monitoring of alpha-ray emitting dust is an important issue for the decommissioning process of the Fukushima Daiichi Nuclear Power Plant to evaluate the shape, nuclides and dose rate of the dust. This information helps workers in the reactor to prevent internal exposure from alpha-ray emitting dust, and we have developed this monitor consisting of a scintillation material and an imaging detector. We have searched for suitable materials for the imaging, and Cs 3 Cu 2 I 5 is one of the candidates, and an imaging test was operated with these materials. Cs 3 Cu 2 I 5 crystals grown by the vertical Bridgman Stockbarger method were crushed into the powders, and the powders were applied to the scintillation sheet. The Radioluminescence spectrum by alpha-ray excitation was obtained with an emission wavelength of approximately 430 nm, and alpha-ray images were obtained with the sheet and Complementary Metal Oxide Semiconductor (CMOS) camera.