Electron cyclotron heating assisted startup in JT-60U

Kajiwara, Ken*; Ikeda, Yoshitaka; Seki, Masami; Moriyama, Shinichi; Oikawa, Toshihiro; Fujii, Tsuneyuki; JT-60 Team

Nuclear Fusion, 45(7), p.694 - 705, 2005/07

https://doi.org/10.1088/0029-5515/45/7/019

Electron cyclotron heating (ECH) assisted start-up experiment was performed in JT-60U. The breakdown loop voltage, becoming the maximum value at the plasma start-up, successfully reduced from 30 V to 4 V (E = 0.26 V/m) by 200 kW ECH. This fulfills the value less than 0.3 V/m, which corresponds to the maximum electric field required in ITER. Moreover, in order to investigate properties of start-up plasmas, parameter scans of the ECH power, prefilled gas pressure, resonant position, polarization angle and injection position were carried out and the dependence on them were obtained. It was revealed that the properties have dependences on the injection position and polarization angle in large tokamaks although they seemed to have no dependence on them from the experiments in small and medium tokamaks. In addition, in experiments of the plasma start-up using second and third harmonic ECH, it was found that the plasma current was ramped by 800 kW second harmonic ECH and was not ramped by 1.6 MW third harmonic ECH even with 7 MW neutral beam injection heating.

25-J green-beam generation with large aperture CsLiBO crystals

Kiriyama, Hiromitsu; Inoue, Norihiro*; Yagi, Kenichi*; Nagai, Toru*; Aoyama, Makoto; Yamakawa, Koichi

Proceedings of Conference on Lasers and Electro-Optics / Quantum Electronics and Laser Science Conference (CLEO/QELS 2002), p.CPDC6_1 - CPDC6_3, 2002/00

no abstracts in English

High efficiency second-harmonic generation in multi-pass quadrature arrangement

Kiriyama, Hiromitsu; Nakano, Fumihiko*; Yamakawa, Koichi

JAERI-Research 2001-030, 26 Pages, 2001/05

JAERI-Research-2001-030.pdf:1.14MB

no abstracts in English

Gamma-ray measurements in JT-60U ICRF heated plasma

Kondoh, Takashi; Kimura, Haruyuki; Kusama, Yoshinori; Morioka, Atsuhiko; Moriyama, Shinichi; Saigusa, Mikio; Nagashima, Keisuke; Yoshino, Ryuji; Harano, Hideki*

Purazuma, Kaku Yugo Gakkai-Shi, 72(12), p.1397 - 1405, 1996/12

http://ci.nii.ac.jp/naid/110003826665

no abstracts in English