Electron cyclotron emission measurements in JT-60U

An electron cyclotron emission (ECE) measurement system has been developed to obtain electron temperature with high time and spatial resolution for JT-60U plasmas. The system consists of three different diagnostic systems. These systems have different advantages and have been used complementarily. Several kinds of calibration are periodically carried out in the systems to secure reliable measurements. In order to reduce the transmission loss, a corrugated waveguide transmission line was installed and the reduction of the loss of ca. 3 dB was attained. As preliminary applications toward the operation of future fusion reactors, the feedback control of electron temperature profile and the automatic determination of the sawtooth inversion radius with an adaptive neural network were successfully demonstrated.