Plasma and Fusion Research

Volume 14, 2405043 (2019)

Regular Articles

Performance Test of Double-Disk Type Output Window of 28/35 GHz Dual-Frequency Gyrotron for CW Operation
Maki OKADA, Tsuyoshi KARIYA, Tsuyoshi IMAI, Ryutaro MINAMI, Tomoharu NUMAKURA, Yuto EBASHI, Fumiya MOTOYOSHI and Yousuke NAKASHIMA
Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
(Received 29 September 2018 / Accepted 25 December 2018 / Published 25 February 2019)


A 28 GHz/35 GHz dual-frequency gyrotron has been developed for use by the University of Tsukuba and its collaborative research institutions. This gyrotron incorporates a sapphire double disk window for 28 GHz- 0.4 MW-Continuous Wave (CW) operation. The heat transfer coefficient was estimated by comparing the measurement results of the output window temperature with calculated values and the results suggest that this gyrotron can operate in the CW operation.


gyrotron, ECH system, millimeter wave, 28 GHz, 35 GHz, CW operation, double-disk window

DOI: 10.1585/pfr.14.2405043


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