ABSTRACT
High-resolution neutron radiography provides novel and stirring opportunities to investigate the structures of light elements encased by heavy elements. For this study, a series of Gd2O2S:Tb, F particles were prepared using a high-temperature solid phase method and then used as a scintillation screen. Upon reaching 293 nm excitation, a bright green emission originated from the Tb3+ luminescence center. The level of F doping affected the fluorescence intensity. When the F doping level was 8 mol%, the fluorescence intensity was at its highest. The absolute quantum yield of the synthesized particles reached as high as 77.21%. Gd2O2S:Tb, F particles were applied to the scintillation screen, showing a resolution on the neutron radiograph as high as 12 µm. These results suggest that the highly efficient Gd2O2S:Tb, F particles are promising scintillators for the purposes of cold neutron radiography.
Subject(s)
Metals, Rare Earth , Radiography , GadoliniumABSTRACT
A novel non-destructive testing scanning system based on a large-size line array fast neutron detector and compact D-T neutron source has been constructed. The scanning range is up to 1000 mm, and the resolution is better than 1 mm. The fast neutron detection subsystem consists of a polypropylene zinc sulfide scintillator embedded with wavelength-shifting fibers, coupled with a light lens and a scientific CCD camera. With a new rotating tritium target, the lifetime of the compact D-T neutron source could achieve ten hours. The experimental results indicate that the scanning method based on line array fast neutron detector and D-T neutron source is feasible and enables the detection of slits on the order of 0.5 mm in width. Fast neutron tomography has been realized by this detection system too.
ABSTRACT
A moveable multi-use neutron imaging facility was constructed based on a compact accelerator D-T neutron source, for use in thermal and fast neutron radiography and tomography. Experiments were carried out to investigate the imaging quality for different standard samples. The smallest width of a slit that can be tested by digitized thermal neutron radiography was found to be 0.06 mm, while the smallest diameter of holes tested by digitized fast neutron radiography was 0.5 mm. A gadolinium wire of 0.2 mm in diameter within a multi-material structure was reconstructed clearly with thermal neutron tomography, and holes in a light material were reconstructed with fast neutron tomography.
