Nondestructive isotope detection by using laser compton scattering gamma-ray based nuclear resonance fluorescence

Progress in laser physics and accelerator physics has enabled us to use a new generation gamma-ray beam, namely laser Compton scattering (L/Cs) gamma-ray beam. The L/Cs gamma-ray beam has advantages that are an energy-tunable quasi-monochromatic gamma-ray beam. We have studied a nondestructive assay using nuclear resonance fluorescence with a LCS gamma-ray beam. This assay can be applied to the detection of nuclear materials hidden in cargo or a container. By measuring the amounts of the levels of oxygen, nitrogen, and carbon, the type of explosive can also be identified. We have demonstrated the detection of lead or melamine hidden in iron shields with thicknesses of 10-15 mm. Advanced laser technology is crucial to realize a compact gamma-ray source that can be installed in seaports. (author)