Development of EC launcher and diamond window for ITER

Takahashi, Koji; Sakamoto, Keishi; Imai, Tsuyoshi; Kasugai, Atsushi; Heidinger, R.*; Thumm, M.*; Moeller, C. P.*

A front steering (FS) launcher and a remote steering (RS) one have been studied for ITER. In the analysis of a mirror(Cu alloy) for FS launcher, max. temperature of 333C and max. induced stress of 136MPa, less than allowable stress(200MPa), were obtained at the mirror surface under 1MW/1line in CW operation. The efficient transmission (95%) at -1212 and 170GHz was performed for both polarizations in the experiments of a square corrugated waveguide for the RS launcher. RF and pressure tests of the diamond window irradiated by neutron were carried under JA/EU(FZK) collaboration. Neutron fluence of the window was 10n/m, whereas the estimated annual fluence at the window position is 1010n/m. Transmission of 0.48MW-30sec and 0.2MW-132sec were performed. It was successfully demonstrated that the irradiated window withstood 0.4MPa, which was twice higher than the ITER requirement. Diamond windows are applicable for ITER.