Progress in long-pulse production of powerful negative ion beams for JT-60SA and ITER

Kojima, Atsushi; Umeda, Naotaka; Hanada, Masaya; Yoshida, Masafumi; Kashiwagi, Mieko; Tobari, Hiroyuki; Watanabe, Kazuhiro; Akino, Noboru; Komata, Masao; Mogaki, Kazuhiko; et al.

Nuclear Fusion, 55(6), p.063006_1 - 063006_9, 2015/06

https://doi.org/10.1088/0029-5515/55/6/063006

Significant progresses in the extension of pulse durations of powerful negative ion beams have been made to realize the neutral beam injectors for JT-60SA and ITER. In order to overcome common issues of the long pulse production/acceleration of negative ion beams in JT-60SA and ITER, the new technologies have been developed in the JT-60SA ion source and the MeV accelerator in Japan Atomic Energy Agency. As for the long pulse production of high-current negative ions for JT-60SA ion source, the pulse durations have been successfully increased from 30 s at 13 A on JT-60U to 100 s at 15 A by modifying the JT-60SA ion source, which satisfies the required pulse duration of 100 s and 70% of the rated beam current for JT-60SA. This progress was based on the R&D efforts for the temperature control of the plasma grid and uniform negative ion productions with the modified tent-shaped filter field configuration. Moreover, the each parameter of the required beam energy, current and pulse has been achieved individually by these R&D efforts. The developed techniques are useful to design the ITER ion source because the sustainment of the cesium coverage in large extraction area is one of the common issues between JT-60SA and ITER. As for the long pulse acceleration of high power density beams in the MeV accelerator for ITER, the pulse duration of MeV-class negative ion beams has been extended by more than 2 orders of magnitude by modifying the extraction grid with a high cooling capability and a high-transmission of negative ions. A long pulse acceleration of 60 s has been achieved at 70 MW/m (683 keV, 100 A/m) which has reached to the power density of JT-60SA level of 65 MW/m.

High current negative ion production in a low-pressure discharge

Morishita, Takatoshi; Kashiwagi, Mieko; Okumura, Yoshikazu; Watanabe, Kazuhiro; Hanada, Masaya; Inoue, Takashi; Imai, Tsuyoshi

Dai-12-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu (BEAMS 2001) Hobunshu, p.33 - 36, 2001/11

no abstracts in English

Development of a dc 1MV transmission line for the ITER neutral beam injector

Watanabe, Kazuhiro; Okumura, Yoshikazu; Ono, Yoichi*; Tanaka, Masanobu*

Heisei-13-Nen Denki Gakkai Zenkoku Taikai Koen Rombunshu, P. 3081, 2001/03

no abstracts in English

Nuclear and thermal calculations on a hybrid system combining a proton accelerator and a fission reactor core; Study of energy conversion system

;

PNC TN9410 97-029, 39 Pages, 1997/03

PNC-TN9410-97-029.pdf:2.58MB

At present, a high power CW(Continuous Wave) electron linac accelerator is under development in PNC as a part of transmutation study by accelerators. Last year we performed nuclear and thermal calculation on a hybrid reactor system combining the electron linac and a subcritical core with TRU fuel as one of applied uses. It is well known that the hybrid reactor system can also use a proton accelerator instead of the electron one. The nuclear and thermal calculation was performed on the system using the proton accelerator in this year. Comparison of the extinguished quantity of TRU fuel was performed between calculation results of both systems. In the proton linac hybrid system, a proton beam accelerated from the linac is injected into a target located in the center of the subcritical core to produce neutrons by spallation reactions. The neutrons enter the surrounding subcritical core to extinguish the TRU. The result of calculation showed that the extinguished quantity of TRU was about 10 kg where the proton beam power of 100 MW injected into the subcritical core system of keff = 0.95 over 1 year. The extinguished quantity of TRU was about 100 times as large as that in the case studied last year on the electron linac hybrid system.

Physical design of JT-60 super upgrade

Nagashima, Keisuke; Kikuchi, Mitsuru; ; Ozeki, Takahisa; Aoyagi, Tetsuo; Ushigusa, Kenkichi; Neyatani, Yuzuru; Kubo, Hirotaka; Mori, Katsuharu*; *; et al.

Fusion Engineering and Design, 36(2-3), p.325 - 342, 1997/00

https://doi.org/10.1016/S0920-3796(96)00698-9

no abstracts in English

Investigation of high-n TAE modes excited by minority-ion cyclotron heating in JT-60U

Saigusa, Mikio; Kimura, Haruyuki; Moriyama, Shinichi; Neyatani, Yuzuru; Fujii, Tsuneyuki; Koide, Yoshihiko; Kondoh, Takashi; Sato, Masayasu; Nemoto, Masahiro; Kamada, Yutaka; et al.

Plasma Physics and Controlled Fusion, 37, p.295 - 313, 1995/00

https://doi.org/10.1088/0741-3335/37/3/009

no abstracts in English

Ion temperature profile simulation of JT-60 and TFTR plasmas with ion temperature gradient mode transport models

Shirai, Hiroshi; Hirayama, Toshio; Koide, Yoshihiko; Yoshida, Hidetoshi; Naito, Osamu; Sato, Masayasu; Fukuda, Takeshi; Sugie, Tatsuo; Azumi, Masafumi; D.R.Mikkelsen*; et al.

Nuclear Fusion, 34(5), p.703 - 727, 1994/00

https://doi.org/10.1088/0029-5515/34/5/I09

no abstracts in English

Development of acceleration power supplies of a neutral beam injection system using GTO switches with transient-voltage regulation capability

Matsuoka, Mamoru; *; Matsuda, Shinzaburo; *; Mizuno, Makoto; *; Watanabe, Kazuhiro; *

Denki Gakkai Rombunshi, B, 112(11), p.1035 - 1044, 1992/00

no abstracts in English

Analysis of pressure distribution in JT-60 neutral beam injector by Monte Carlo method

Shibanuma, Kiyoshi

Shinku, 34(8), p.645 - 652, 1991/00

https://doi.org/10.3131/jvsj.34.645

no abstracts in English

Beam-energy control during a beam pulse in a neutral beam injection system

Matsuoka, Mamoru; Akiba, Masato; *; Horiike, Hiroshi; Kuriyama, Masaaki; Matsuda, Shinzaburo; Ohara, Yoshihiro

Review of Scientific Instruments, 61(10), p.2614 - 2622, 1990/10

https://doi.org/10.1063/1.1141847

no abstracts in English