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Infrared (IR) thermography is a useful diagnostic tool for measuring surface temperatures on divertor plates by using light emitted in the IR range. Japan plans to procure and develop divertor IR thermography for the ITER project. The system design, optical design, and evaluation of detected photons have already been conducted. All optical devices will be installed in the occupied space without interfering with other devices. The required spatial resolution of 3mm on divertor plates is satisfied by the designed optics. The gamma-ray dose rate at 106 s after shutdown of operations (shutdown dose rate) in the interspace is low (15 20 μSv/h). Two color detectors and a spectroscopic system are designed using mirrors with high reflectivity in the range 1 5 μm. From the evaluation of detected photons, sufficient photons at 3 and 5 μm can be detected at low emissivity (e = 0.2).

Fusion power output of ITER is measured by a group of neutron flux monitors combined with a neutron activation system and neutron profile monitors. These systems should be absolutely calibrated by use of DD/DT generators moving inside the ITER vacuum vessel (in-situ calibration). Each neutron monitor has a limited measurement range of emission rate, but the ranges are connected by cross-calibration using the ITER plasma with at least one decade overlapping. The over all dynamic range covered by the group of neutron flux monitors is 10 14 n/sec to 10 21 n/sec. Effects of vertical/radial movement of plasma on the measurement accuracy were reviewed. It was found that cross-calibration using specially planned jog shots, and a vertical neutron camera is important to minimize the inaccuracy caused by the plasma movement.

First results from nonlinear simulations of energetic particle modes and the resulting transport of energetic ions using realistic tokamak geometry are presented and compared with results obtained with a shifted-circle model equilibrium and otherwise equivalent parameters. The modes excited in both cases have similar frequen- cies and mode structuresand cause a similar amount of energetic ion transport during the first few hundred Alfven times of the nonlinear evolution. The similarity in transport is interesting since it stands in contrast to the reduced linear growth rate and saturation level in the non-circular case: for the parameters chosen, both are reduced by a factor of 2 compared to the circular case. These results motivate further studies, including a verification of our results with other codes, a clarification of the mechanisms underlying the linear stabilization, and a detailed analysis of the mode activity and particle redistribution during the nonlinear evolution.

This paper describes diagnostics for transport analysis of energetic ions in JT-60U. Line integrated neutron emission profiles are measured using Stilbene neutron detectors, which are installed as a neutron emission profile monitor. The flux and energy distribution of charge exchange neutral particles are measured using a natural diamond detector (NDD). These measurements in the presence of bursting instabilities in the frequency range of Alfven Eigenmode induced by negative-ion-based neutral beam injection, which are called Abrupt Large-amplitude Events, indicate that energetic ions are transported from the core region in the plasma due to a resonance interaction between energetic ions and the instabilities. Development of a digital signal processing (DSP) system for a neutron detector and a NDD enabling a sampling rate in the MHz class is proceeding. The DSP system for the neutron detector successfully discriminates between neutrons and gamma-rays in tests using neutron/gamma-ray sources.