Development of gradient-curvature measurements and study of spatio-temporal structure

• Project/Area Number: 26630474
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: National Institute for Fusion Science
• Principal Investigator: TOKUZAWA TOKIHIKO 核融合科学研究所, ヘリカル研究部, 准教授 (90311208)
• Co-Investigator(Renkei-kenkyūsha): KOGI Yuichiro 福岡工業大学, 工学部, 教授 (10398109) ; SHIMIZU Akihiro 核融合科学研究所, ヘリカル研究部, 助教 (00390633)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: プラズマ計測 / ミリ波 / 勾配 / 曲率 / 時空間構造

Outline of Final Research Achievements

We developed the diagnostics system for measuring the gradient and curvature of the electron temperature and the electron density profiles in high-temperature plasma. Because the gradient and curvature of the plasma are considered to affect the plasma confinement, this measurement is important for the the study of fusion plasma science. We performed the diagnostics in the large helical device (LHD) plasma and have successfully obtained the temporal behavior of these parameter. Comparing with the conventional diagnostics, the characteristics of this technique has been clarified.

Research Products

• [Journal Article] Turbulence in edge and core transport barriers: new experimental results and modeling (2017)
  • Author(s): T.Tokuzawa
  • Journal Title: Nuclear Fusion Volume: 57 Issue: 2 Pages: 025001-025001
  • DOI: 10.1088/0029-5515/57/2/025001
  • NAID: 120007149369
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Distorted magnetic island formation during slowing down to mode locking in helical plasmas (2017)
  • Author(s): T. Tokuzawa, Y. Takemura, K.Y. Watanabe, S. Sakakibara, Y. Narushima, H. Tsuchiya, Y. Nagayama, S. Inagaki, K. Ida, M. Yoshinuma, K. Tanaka, Y. Suzuki, I. Yamada, and the LHD Experiment Group
  • Journal Title: Nuclear Fusion Volume: ５７ Issue: 7 Pages: 076003-076003
  • DOI: 10.1088/1741-4326/aa6d26
  • NAID: 120007029203
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Developments of frequency comb microwave reflectometer for the interchange mode observations in LHD plasma (2016)
  • Author(s): R. Soga, T. Tokuzawa, K.Y. Watanabe, K. Tanaka, I. Yamada, S. Inagaki and N. Kasuya
  • Journal Title: Journal of Instrumentation Volume: 11 Issue: 02 Pages: C02009-C02009
  • DOI: 10.1088/1748-0221/11/02/c02009
  • NAID: 120007180053
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Observation of electron temperature turbulence with a correlation electron cyclotron emission radiometer on LHD (2016)
  • Author(s): Y. Kogi, T. Higashi, N. Tamura, H. Tsuchiya, D. Kuwahara, Y. Nagayama, A. Mase, K. Takehara and T. Tokuzawa
  • Journal Title: Journal of Instrumentation Volume: Vol. 11 Issue: 01 Pages: C01072-C01072
  • DOI: 10.1088/1748-0221/11/01/c01072
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] LHDにおけるロックドモード様不安定性発現時のプラズマ回転速度変化の観測 (2016)
  • Author(s): 徳沢季彦, 武村勇輝, 渡邊清政, 居田克巳, 吉沼幹朗, 榊原悟, 成嶋吉朗, 土屋隼人, 長山好夫, LHD実験グループ
  • Organizer: 第33回 プラズマ・核融合学会 年会
  • Place of Presentation: 東北大学
  • Year and Date: 2016-11-29
• [Presentation] Magnetic island formation in locked-like mode in helical plasmas (2016)
  • Author(s): T. Tokuzawa, Y. Takemura, K.W. Watanabe, S. Sakakibara, Y. Narushima, H. Tsuchiya, Y. Nagayama, S. Inagaki, K. Ida, M. Yoshinuma, K. Tanaka, Y. Suzuki, I. Yamada, and LHD Experiment Group
  • Organizer: 26th IAEA Fusion Energy Conference
  • Place of Presentation: 京都
  • Year and Date: 2016-10-17
  • Int'l Joint Research
• [Presentation] Observation of oscillation of poloidal rotation velocity in LHD (2016)
  • Author(s): T. Tokuzawa, Y. Takemura, K.W. Watanabe, S. Inagaki, K. Ida, M. Yoshinuma, S. Sakakibara, Y. Narushima, H. Tsuchiya, Y. Nagayama, K. Tanaka, I. Yamada, and LHD Experiment Group
  • Organizer: 18th International Congress on Plasma Physics
  • Place of Presentation: Kaohsiung, Taiwan
  • Year and Date: 2016-06-27
  • Int'l Joint Research
• [Presentation] マイクロ波計測器から得られる大規模データを用いた乱流プラズマの特性抽出法の開発 (2016)
  • Author(s): 徳沢季彦
  • Organizer: RIAMフォーラム2016
  • Place of Presentation: 九州大学
  • Year and Date: 2016-06-02
  • Invited
• [Presentation] 磁場閉じ込めプラズマの周辺部ポロイダル速度の時空間構造変化の観測 (2016)
  • Author(s): 徳沢季彦，曽我良太，竹原啓太，稲垣滋，小波蔵純子，吉川正志，居田克巳， 渡邊清政，武村勇輝，土屋隼人，ＬＨＤ実験グループ
  • Organizer: 日本物理学会 第71回年次大会
  • Place of Presentation: 東北学院大学 泉キャンパス
  • Year and Date: 2016-03-19
• [Presentation] 高空間分解ECE計測のためのLHD真空容器内に設置する金属レンズアンテナの開発 (2016)
  • Author(s): 竹原啓太 , 徳沢季彦, 渡邉清政, LHD実験グループ
  • Organizer: 日本物理学会 第71回年次大会
  • Place of Presentation: 東北学院大学 泉キャンパス
  • Year and Date: 2016-03-19
• [Presentation] Turbulence in edge and core transport barriers, new experimental results and modeling (2015)
  • Author(s): T.Tokuzawa
  • Organizer: 15th International Workshop on H-mode Physics and Transport Barriers
  • Place of Presentation: Garching, Germany
  • Year and Date: 2015-10-19
  • Int'l Joint Research / Invited
• [Presentation] Application study for magnetically confined fusion plasma diagnostics using pulsed terahertz waves (2015)
  • Author(s): T. Tokuzawa, Y. Kadoya, M. Tani, K. Yamamoto,M. Hangyo, H. Kitahara, J. Kohagura, M. Yoshikawa, H. Idei, M. Nishiura, K. Tanaka, I. Yamada, and K. Kawahata
  • Organizer: 17th International Symposium on Laser-Aided Plasma Diagnostics
  • Place of Presentation: Sapporo, Japan
  • Year and Date: 2015-09-27
  • Int'l Joint Research
• [Presentation] Upgraded Frequency Comb Reflectometer System Utilizing Both Ka-band and U-band Microwave in LHD (2015)
  • Author(s): T. Tokuzawa, R. Soga, S. Inagaki, K. Y. Watanabe, K. Tanaka, I. Yamada, N. Kasuya, K. Ida, K. Itoh, A. Ejiri, K. Kawahata, and LHD Experiment Group
  • Organizer: 12th International Reflectometry Workshop
  • Place of Presentation: Jülich, Germany
  • Year and Date: 2015-05-18
  • Int'l Joint Research
• [Presentation] ＬＨＤプラズマにおける交換型不安定性の観測とその構造に関する研究 (2015)
  • Author(s): 曽我良太,徳沢季彦,渡邊清政
  • Organizer: 日本物理学会 第70回年次大会
  • Place of Presentation: 早稲田大学
  • Year and Date: 2015-03-21 – 2015-03-24
• [Presentation] マイクロ波計測器信号からの乱流揺動信号抽出法の研究 (2015)
  • Author(s): 徳沢季彦
  • Organizer: 九州大学応用力学研究所研究会「プラズマ乱流実験の大容量データからの物理情報抽出新手法の開発」
  • Place of Presentation: 九州大学
  • Year and Date: 2015-02-27
• [Presentation] Multi-point Measurements for Study of Plasma Turbulence in the LHD (2014)
  • Author(s): T. Tokuzawa, S. Inagaki, A. Ejiri, R. Soga, I.Yamada, S. Kubo, M.Yoshinuma, K. Ida, C.Suzuki, K. Tanaka, T. Akiyama, N. Kasuya, K. Itoh, K.Watanabe, H. Yamada, K. Kawahata, and LHD EXPERIMENT GROUP
  • Organizer: Plasma Conference 2014
  • Place of Presentation: 朱鷺メッセ、新潟県
  • Year and Date: 2014-11-18 – 2014-11-21
  • Invited