Design and development of EC H&CD antenna mirrors for ITER

Takahashi, Koji; Kobayashi, Noriyuki*; Kasugai, Atsushi; Sakamoto, Keishi

In the ITER, an EC H&CD steering antenna mirror was designed to reflect eight or nine 1MW-wave beams. The cross-section and thickness of the mirror are 250360 mm and 50mm, respectively. The thermal and stress analysis under the ITER condition show that the copper alloy(DSCu) mirror with stainless steel cooling tubes inside is considered acceptable. The EC H&CD antenna system for the ITER must have a dog-legged transmission lines so as to protect the diamond windows or superconducting magnets of a tokamak. A 90 miter bend, which consists of waveguides and a reflection mirror, is required to make the structure. The mock-up of the mirror based on the ITER design was fabricated and the high power transmission experiment was carried out. The mm-wave transmission with power/pulse length 450kW/5.0sec, was demonstrated. The ohmic loss is estimated to be 0.2%, which agrees with the calculation based on electrical resistivity of DSCu 2.010m.