Utilization program of MK-III and its prospects

JOYO in now in the final stage of the MK-III modification program. It will start MK-III core operation in the spring 2004. Various programs have been made to utilize the MK-III core, which will be reflected in the Feasibility Study on Commercialized Fast Reactor Cycle Systems, ''MONJU'' and so forth. The programs include irradiation tests for high burnup fuel up to 150 GWd/t, minor actinide containing fuel, advanced fuels such as metal fuel, Vipac fuel, and a self-actuated reactor shut-down system. In other aspect, JOYO has become valuable as a fast neutron irradiation facility world wide, it should be utilized not only in the development of Japanese fast reactor cycle systems, but also in international study on basic science and technology. (author)