Investigation of 4 mm microwave scattering measurement in TRIAM-1

Investigation of microwave scattering measurement at the turbulent heating of TRIAM-1 was performed. A linearized Vlasov equation for homogeneous plasma in a magnetic field was used for the study of instability. The current-driven instability consists of ion acoustic instability and electrostatic ion cyclotron wave instability. The growth rate of the ion cyclotron instability was faster than that of the ion acoustic instability in TRIAM-1. The measurement of microwaves scattered by the density fluctuation due to the instability was carried out. The measurement of scattered waves at 90 degree was able to detect the fundamental and second harmonic waves of the static ion cyclotron instability. Preliminary experiment with a homodyne type microwave circuit showed good performance. (Kato, T.)