Mode purity and beam profile measurement of ITER equatorial launche

ITER水平ポートランチャーにおけるモード成分とビームプロファイルの計測

小田 靖久; 高橋 幸司; 福成 雅史*; 梶原 健; 小林 貴之; 森山 伸一; 坂本 慶司

Oda, Yasuhisa; Takahashi, Koji; Fukunari, Masafumi*; Kajiwara, Ken; Kobayashi, Takayuki; Moriyama, Shinichi; Sakamoto, Keishi

ITER equatorial launcher (EL) for EC HCD is designed based on quasi-optical beam transmission and mode purity is important parameter for its transmission efficiency. In JAEA, mode conversion by ITER relevant TL system and ITER equatorial launcher (EL) mock-up was studied. Firstly mode content of TL output was measured using 40 m long distance TL test stand and mode conversion caused by cold TL component was obtained. Next mode content was also measured after 600 kW / 200 s long pulse operation. As a result, mode conversion of hot TL was increased by 10 from the result. The mode purity at EL mock-up was measured with low power test system. Measurement of beam profile of waveguide output deduced the mode conversion in mock-up system. Then beam profile at quasi-optical transmission and stray RF field of the beam duct wall were measured.