Present status of neutron application research. Neutron radiography

Neutron radiography is an important technique complementarily used with X-ray radiography. While X-ray attenuates dependent on atomic number, neutron effectively attenuates by a few specific elements among all hydrogen, resulting in clear visibility of organic materials or water in neutron radiographys. At the present time, neutron radiography is one of the main non-destructive testing techniques which are able to satisfy the quality-control requirements of explosive devices used in space programs. For the detonating devices the detection of cracks of 0.1 mm thickness in the explosion. The facilities frequently used for neutron radiography in Japan such as JRR-3M reactor of Japan Atomic Energy Research Institute, KUR of Kyoto University, Kumatori, and a baby cyclotron of Sumitomo Industry which provides neutrons from reaction of 18 MeV proton beams with beryllium are briefly introduced together with specific performance of respective equipments as radiography, for example, the availability of cold neutrons, a fast video camera with image intensifier, and gadolinium converters. Some examples of industrial applications of neutron radiography are given. (S. Ohno)