Annual report of the Division of Thermonuclear Fusion Research, JAERI

Works performed in the Division of Thermonuclear Fusion Research for the period of April 1974 to March 1975 are described. (1) In JFT-2, power-up work of the generator to increase the toroidal magnetic field from 10 kG to 18 kG was completed in October 1974, and the JFT-2 phase-II experiment started. (2) A JFT-2a tokamak of a tear-drop cross-section with axisymmetric divertor was put into operation in August 1974, as scheduled. Initial experiments confirmed that the plasma enclosed inside a separatrix magnetic surface was stably produced. (3) In the diagnostics, a data processing system and a multi-channel particle analyzer were fabricated and put into operation. (4) A test stand (ITS-1) for the development of neutral beam injectors was assembled, and the preliminary experiment on an ion source started in February 1975. (5) In design study of a large tokamak device JT-60, the preliminary design was completed under contract with the industry. Physical studies on the plasma confinement in JT-60 and refinement and improvement of the design continued. (6) Theoretical and computational works continued in neutral injection heating, impurity transport, relaxation of radial electric field and mhd stability. (7) The design of a 2000 MW fusion power reactor which started in the previous year was further improved. The concept and design criteria of an experimental power reactor were studied. (auth.)