Tritium measurement II—tritium in plasma

Abstract

In D–T burning plasma, the fueled ion density ratio nD/nT is a key parameter to control the fusion output power. The requirements in ITER are briefly described, namely the range of density ratio, spatial locations (core, edge, wall, and divertor), and spatial/time resolutions. Diagnostic methods on neutrons from D–T reactions, the radio waves sensitive to the effective mass, charge exchange neutral flux of fuel particles, and passive and active spectroscopies for Balmer–Fulcher lines of fuel neutrals are introduced. Diagnostic principles, instrument of measurements, experimental results achieved in experimental devices, and prospects for ITER are described for each method.