Non-destructive Nuclear Detection And Measurent Technology Development Projects Of JAEA For Nuclear Non-prolifiration And Security

The Japan atomic energy agency (JAEA) is implementing technological development projects on non-destructive assay (NDA) for nuclear detection and measurement under the support of the subsidy for "promotion of strengthening nuclear security or the like" of the Japanese government MEXT (Ministry of education, culture, sports, science and technology). In this presentation, some of the projects are briefly overviewed.One of the programs is “development of nuclear resonance fluorescence (NRF) technique” for measurement/detection of nuclear material. This technique utilizes quasi monochromatic gamma-rays. The nuclide of interest resonantly absorbs photons to be excited and then emits gamma rays to be de-excited. Because nuclear resonance transitions are unique to each nuclide, and the penetration ability of gamma-ray beams is high, this technique would be useful for detection or analysis of specific nuclides even inside obstructing materials. Developments have been performed in (1) methodological concept, (2) generation of intense and quasi-monochromatic gamma ray generation, and (3) simulation tools for NRF and elastic scattering of high-energy photon. An experiment was perfumed to demonstrate detection of a material shielded in an iron container at the NewSUBARU facility of Hyogo University.Another program is “development of active neutron NDA techniques”, in which four techniques utilizing neutron interrogation methods are under developed: i.e., Differential Die Away Analysis (DDA), Delayed Gamma-ray Analysis (DGA), Neutron Resonance Transmission Analysis (NRTA), and Prompt Gamma-ray Analysis (PGA). These techniques are used to achieve complement information of a sample material. They would be useful for nuclear material accountancy, applicable to both low- and high-level radioactive nuclear materials (NMs), and for nuclear security purposes such as detection of NM and explosive materials.Another program is “Development of quick-response and broad-area covering nuclear and radioactive material detection technologies”. Developments of passive gamma ray and neutron detection systems has been started: e. g. a portable gamma-ray spectrometer combined with GPS and the other sensors, a compact and light Compton camera mountable on a drone, and a fast neutron detector system.