Laboratory experiment of magnetic reconnection under strong guide field to investigate generation process of energetic electrons

• Project/Area Number: 26287143
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Plasma science
• Research Institution: The University of Tokyo
• Principal Investigator: INOMOTO Michiaki 東京大学, 大学院新領域創成科学研究科, 准教授 (00324799)
• Co-Investigator(Kenkyū-buntansha): 小野 靖 東京大学, 大学院新領域創成科学研究科, 教授 (30214191) ; 今田 晋亮 名古屋大学, 宇宙地球環境研究所, 講師 (40547965) ; 神尾 修治 核融合科学研究所, ヘリカル研究部, 助教 (80705525)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥15,990,000 (Direct Cost: ¥12,300,000、Indirect Cost: ¥3,690,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000); Fiscal Year 2016: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2015: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2014: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000)
• Keywords: 宇宙・天体プラズマ / 磁気リコネクション / 粒子加速

Outline of Final Research Achievements

Electron acceleration during magnetic reconnection process under a strong guide field was experimentally investigated by using a variety of diagnostics in axial merging of two torus plasmas. Single sight-line soft X-ray measurement and small energy analyzer revealed that fast electrons with energy higher than 200 eV were generated during the guide field reconnection process. The acceleration region was identified by using the soft X-ray imaging system. The accelerated electrons formed a localized current filament to affect the global magnetic field profile. The acceleration mechanism and its contribution to reconnection process was successfully verified by using axisymmetric experimental configuration.

Research Products

• [Journal Article] Magnetic island dynamics in magnetic reconnection in UTST experiments (2018)
  • Author(s): Kamio S.、Inomoto M.、Yamasaki K.、Yamada T.、Cheng C. Z.、Ono Y.
  • Journal Title: Physics of Plasmas Volume: 25 Issue: 1 Pages: 012126-012126
  • DOI: 10.1063/1.5006092
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Reconstruction of plasma shape and eddy current profile based on modified cauchy condition surface method in merging spherical tokamak (2017)
  • Author(s): T. Ushiki, M. Inomoto, M. Itagaki
  • Journal Title: Fusion Engineering and Design Volume: 122 Pages: 36-41
  • DOI: 10.1016/j.fusengdes.2017.09.012
  • NAID: 120006734151
  • Peer Reviewed
• [Journal Article] Separated Double-Current Layers in a High-Guide-Field Reconnection Experiment (2017)
  • Author(s): Kyohei Kondo, Michiaki Inomoto, Xuehan Guo, Tomohiko Ushiki, Takumichi Sugawara, Takumi Mihara, Shuji Kamio, Hiroshi Tanabe, Yasushi Ono
  • Journal Title: Plasma and Fusion Research Volume: 12 Issue: 0 Pages: 1202033-1202033
  • DOI: 10.1585/pfr.12.1202033
  • NAID: 130006081763
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Energy Flux due to Electromagnetic Fluctuations during Guide Field Magnetic Reconnection (2016)
  • Author(s): Akihiro Kuwahata, Michiaki Inomoto, Ryoma Yanai, Yasushi Ono
  • Journal Title: Plasma and Fusion Research Volume: 11 Issue: 0 Pages: 1301087-1301087
  • DOI: 10.1585/pfr.11.1301087
  • NAID: 130005311583
  • ISSN: 1880-6821
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Characteristics of Magnetic Fluctuations during Magnetic Reconnection in Counter-Helicity Spheromak Merging Experiment (2016)
  • Author(s): Ryoma Yanai, Akihiro Kuwahata, Michiaki Inomoto
  • Journal Title: Plasma and Fusion Research Volume: 11 Issue: 0 Pages: 2401069-2401069
  • DOI: 10.1585/pfr.11.2401069
  • NAID: 130005330457
  • ISSN: 1880-6821
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Generation of Energetic Electrons during Spherical Tokamak Merging in UTST (2016)
  • Author(s): Tomohiko USHIKI, Michiaki INOMOTO, Kotaro YAMASAKI, Xuehan GUO, Takumichi SUGAWARA, Keita MATSUYAMA, Haruhisa KOGUCHI and Takuma YAMADA
  • Journal Title: Plasma and Fusion Research Volume: 11 Issue: 0 Pages: 2402100-2402100
  • DOI: 10.1585/pfr.11.2402100
  • NAID: 130005395196
  • ISSN: 1880-6821
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Energy flux due to electromagnetic fluctuations during guide field magnetic reconnection (2016)
  • Author(s): Akihiro Kuwahata, Michiaki Inomoto, Ryoma yanai and Yasushi Ono
  • Journal Title: Plasma and Fusion Research Volume: 印刷中
  • NAID: 130005311583
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Characteristics of Magnetic Fluctuations during Magnetic Reconnection in Counter-helicity Spheromak Merging Experiment (2016)
  • Author(s): Ryoma Yanai, Akihiro Kuwahata and Michiaki Inomoto
  • Journal Title: Plasma and Fusion Research Volume: 印刷中
  • NAID: 130005330457
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Observation and numerical modeling of chromospheric evaporation during the impulsive phase of a solar flare (2015)
  • Author(s): Shinsuke Imada, Izumi Murakami, and Tetsuya Watanabe
  • Journal Title: Physics of Plasmas Volume: 22 Issue: 10 Pages: 101206-101206
  • DOI: 10.1063/1.4932335
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Energetic ion acceleration during magnetic reconnection in the Earth’s magnetotail (2015)
  • Author(s): Shinsuke Imada, Mariko Hirai and Masahiro Hoshino
  • Journal Title: Earth, Planets and Space Volume: 67 Issue: 1 Pages: 203-203
  • DOI: 10.1186/s40623-015-0372-2
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Localized electron heating by strong guide-field magnetic reconnection (2015)
  • Author(s): Xuehan Guo, Michiaki Inomoto, Takumichi Sugawara, Kotaro Yamasaki, Tomohiko Ushiki, Yasushi Ono
  • Journal Title: Physics of Plasmas Volume: 22 Issue: 10 Pages: 101201-101201
  • DOI: 10.1063/1.4932339
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Laboratory study of diffusion region with electron energization during high guide field reconnection (2015)
  • Author(s): K. Yamasaki, S. Inoue, S. Kamio, TG. Watanabe, T. Ushiki, X. Guo, T. Sugawara, K. Matsuyama, N. Kawakami, T. Yamada, M. Inomoto, Y. Ono
  • Journal Title: Physics of Plasmas Volume: 22 Issue: 10 Pages: 101202-101202
  • DOI: 10.1063/1.4932345
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Evaluation of Electron Density and Temperature for Neutral Beam Injection in Spherical Tokamak Plasma Formed by Merging Method (2015)
  • Author(s): 菅原拓路，郭学瀚，井通暁
  • Journal Title: IEEJ Transactions on Fundamentals and Materials Volume: 135 Issue: 11 Pages: 727-728
  • DOI: 10.1541/ieejfms.135.727
  • NAID: 130005106274
  • ISSN: 0385-4205, 1347-5533
  • Peer Reviewed
• [Journal Article] Center-solenoid-free merging start-up of spherical tokamak plasmas in UTST (2015)
  • Author(s): M. Inomoto, T. Watanabe, K. Gi, K. Yamasaki, S. Kamio, R. Imazawa, T. Yamada, X. Guo, T. Ushiki, H. Ishikawa, H. Nakamata, N. Kawakami, T. Sugawara, K. Matsuyama, K. Noma, A. Kuwahata, and H. Tanabe
  • Journal Title: Nuclear Fusion Volume: 55 Issue: 3 Pages: 033013-033013
  • DOI: 10.1088/0029-5515/55/3/033013
  • Peer Reviewed
• [Journal Article] Two-Dimensional Electron Temperature and Density Measurement during Strong Guide-Field Reconnection by using Slide-Type Thomson Scattering System (2015)
  • Author(s): X. Guo, M. Inomoto, T. Sugawara, T. G. Watanabe, K. Yamasaki, T. Ushiki, Y. Ono
  • Journal Title: Plasma and Fusion Research Volume: 10 Issue: 0 Pages: 3402017-3402017
  • DOI: 10.1585/pfr.10.3402017
  • NAID: 130005302921
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Comparison between Hinode/SOT and SDO/HMI, AIA Data for the Study of the Solar Flare Trigger Process (2014)
  • Author(s): Bamba, Yumi; Kusano, Kanya; Imada, Shinsuke; Iida, Yusuke
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 66 SP1 Issue: SP1 Pages: 1-11
  • DOI: 10.1093/pasj/psu092
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] Center-solenoid free start-up of spherical tokamak plasma in UTST (2017)
  • Author(s): M. Inomoto, T. Ushiki, X. Guo, T. Sugawara, K. Kondo, T. Mihara, Y. Minami, Y. Inai, H. Tanabe and Y, Ono
  • Organizer: US-Japan Workshop on Compact Tori 2017
  • Int'l Joint Research
• [Presentation] Development of new experimental device focusing on weakly ionized magnetic reconnection using rotating magnetic field (2017)
  • Author(s): R. Yanai, Y. Takahata, M. Inomoto and T. Asai
  • Organizer: US-Japan Workshop on Compact Tori 2017
  • Int'l Joint Research
• [Presentation] Measurement of electron energy distribution function in rotating magnetic field plasma source (2017)
  • Author(s): Y. Takahata, R. Yanai and M. Inomoto
  • Organizer: US-Japan Workshop on Compact Tori 2017
  • Int'l Joint Research
• [Presentation] Merging Formation of High-beta STs in UTST (2017)
  • Author(s): M. Inomoto, T. Ushiki, X. Guo, T. Sugawara, K. Kondo, T. Mihara, Y. Minami, Y. Inai, H. Tanabe, Y. Ono
  • Organizer: 19th International Spherical Torus Workshop
  • Int'l Joint Research
• [Presentation] UTST球状トカマク合体装置における軟X線二次元計測による合体中の高速電子の観測 (2017)
  • Author(s): 牛木 知彦、三原 卓己、井 通暁、菅原 拓路、近藤 恭平、南 佑典、稲井 優希、田辺 博士、小野 靖、小口 治久、三瓶 明希夫
  • Organizer: Plasma Conference 2017
• [Presentation] UTSTにおける合体生成球状トカマクプラズマに対するNBI加熱の評価 (2017)
  • Author(s): 菅原 拓路、井 通暁、牛木 知彦、郭 学瀚、近藤 恭平、三原 卓巳、稲井 優希、田辺 博士、小野 靖
  • Organizer: Plasma Conference 2017
• [Presentation] 高ガイド磁場リコネクションにおける電流シート構造の詳細観測 (2017)
  • Author(s): 近藤 恭平、井 通暁、牛木 知彦、郭 学瀚、菅原 拓路、三原 卓巳、稲井 優希
  • Organizer: Plasma Conference 2017
• [Presentation] UTSTにおける高ガイド磁場リコネクション時の軟Ｘ線発光分布計測の開発 (2017)
  • Author(s): 三原 卓巳、牛木 知彦、井 通暁、郭 学瀚、菅原 拓路、近藤 恭平、稲井 優希、田辺 博士、小野 靖
  • Organizer: Plasma Conference 2017
• [Presentation] リコネクション点付近におけるイオン加速の非対称性解明に向けたドップラー分光計測の開発 (2017)
  • Author(s): 稲井 優希、菅原 拓路、井 通暁、田辺 博士、小野 靖、神尾 修治
  • Organizer: Plasma Conference 2017
• [Presentation] 回転磁場法を用いた弱電離磁気リコネクション装置の開発 (2017)
  • Author(s): 矢内 亮馬、高畑 宜史、井 通暁
  • Organizer: Plasma Conference 2017
• [Presentation] 回転磁場を用いたプラズマ源のEEDF計測 (2017)
  • Author(s): 高畑 宜史、矢内 亮馬、井 通暁
  • Organizer: Plasma Conference 2017
• [Presentation] UTST装置における球状トカマク合体立ち上げ手法の改善 (2017)
  • Author(s): 井 通暁、牛木 知彦、郭 学瀚、菅原 拓路、近藤 恭平、三原 卓巳、南 佑典、稲井 優希、田辺 博士、小野 靖
  • Organizer: Plasma Conference 2017
• [Presentation] Formation of Closed Flux Surfacces in Recnnection Current Layer by Accelerated Electrons during Merging Start-up of Spherical Tokamak (2016)
  • Author(s): M. Inomoto, K. Yamasaki, T. Ushiki, X. Guo, S. Kamio, R. Yanai, T. Sugawara, Y. Fukai, H. Yamanaka, R. Tamura
  • Organizer: 26th IAEA Fusion Energy Conference
  • Place of Presentation: Kyoto International Conference Center
  • Year and Date: 2016-10-17
  • Int'l Joint Research
• [Presentation] プラズマ合体を用いた球状トカマクの立ち上げと加熱 (2016)
  • Author(s): 井通暁, 牛木知彦, 郭学瀚, 山田琢磨, 神尾修治, 山崎広太郎, 菅原拓路, 深井優介, 山中晴揮, 田村崚, 田辺博士, 小野靖
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14
• [Presentation] UTST合体プラズマにおけるCCS法を用いたプラズマ位置形状および渦電流分布再構成 (2016)
  • Author(s): 牛木知彦, 板垣正文, 井通暁
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14
• [Presentation] UTST球状トカマク合体実験における中性粒子ビーム入射(NBI)追加熱の検証 (2016)
  • Author(s): 深井優介, 牛木知彦, 菅原拓路, 郭学瀚, 井通暁
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14
• [Presentation] Center-Solenoid-Free Merging Start-up of STs by Outer PF coils in UTST (2015)
  • Author(s): Michiaki Inomoto
  • Organizer: 18th International Spherical Torus Workshop
  • Place of Presentation: Princeton (USA)
  • Year and Date: 2015-11-03
  • Int'l Joint Research
• [Presentation] Characteristics of Magnetic Fluctuations during Magnetic Reconnection in Counter-helicity Spheromak Merging Experiment (2015)
  • Author(s): R. Yanai
  • Organizer: 25th International Toki Conference
  • Place of Presentation: セラトピア土岐（岐阜県土岐市）
  • Year and Date: 2015-11-03
  • Int'l Joint Research
• [Presentation] Generation of Energetic Electrons during Spherical Tokamak Merging in UTST (2015)
  • Author(s): T. Ushiki
  • Organizer: 25th International Toki Conference
  • Place of Presentation: セラトピア土岐（岐阜県土岐市）
  • Year and Date: 2015-11-03
  • Int'l Joint Research
• [Presentation] Merging formation of high-beta ST as a target plasma for NBI (2015)
  • Author(s): Michiaki Inomoto
  • Organizer: 2015 US-Japan Compact Torus Workshop
  • Place of Presentation: 東武ホテルレバント東京（東京都墨田区）
  • Year and Date: 2015-09-08
  • Int'l Joint Research
• [Presentation] 高ガイド磁場下での磁気リコネクション点における電子エネルギー分布計測 (2015)
  • Author(s): 松山敬太、牛木知彦、山崎広太郎、井通暁
  • Organizer: 平成27年 電気学会 全国大会
  • Place of Presentation: 東京都市大学（東京都世田谷区）
  • Year and Date: 2015-03-26
• [Presentation] Study of Electron Acceleration during Spherical Tokamak Merging in UTST device (2014)
  • Author(s): T. Ushiki, H. Furui, K. Matsuyama, H. Koguchi, M. Inomoto, Y.Ono
  • Organizer: 3rd A3 Foresight Workshop on Spherical Torus (ST)
  • Place of Presentation: オークラアカデミアパークホテル（千葉県木更津市）
  • Year and Date: 2014-12-16
• [Presentation] Slide-type 2-D Thomson scattering measurement for magnetic reconnection in UTST merging experiment (2014)
  • Author(s): X. Guo, M. Inomoto, T. Sugawara, K. Yamasaki, T. Ushiki, H. Nakamata, H. Ishikawa, Y. Ono
  • Organizer: 3rd A3 Foresight Workshop on Spherical Torus (ST)
  • Place of Presentation: オークラアカデミアパークホテル（千葉県木更津市）
  • Year and Date: 2014-12-16
• [Presentation] Overview of UTST Research (2014)
  • Author(s): M. Inomoto and UTST team
  • Organizer: 3rd A3 Foresight Workshop on Spherical Torus (ST)
  • Place of Presentation: オークラアカデミアパークホテル（千葉県木更津市）
  • Year and Date: 2014-12-15
• [Presentation] Relaxation of electron temperature and density profiles after merging startup in UTST (2014)
  • Author(s): T. Sugawara, M. Inomoto, X. Guo, H. Tanabe, T. G. Watanabe, K. Yamasaki, T. Ushiki, H. Nakamata, H. Ishikawa, K. Matsuyama, N. Kawakami, Y. Ono
  • Organizer: 3rd A3 Foresight Workshop on Spherical Torus (ST)
  • Place of Presentation: オークラアカデミアパークホテル（千葉県木更津市）
  • Year and Date: 2014-12-15
• [Presentation] High-beta spherical tokamak start-up by using outer PF coils and plasma merging in UTST (2014)
  • Author(s): M. Inomoto, T.G. Watanabe, K. Yamasaki, T. Ushiki, X. Guo, H. Ishikawa, H. Nakamata, Y. Ono
  • Organizer: Plasma conference 2014
  • Place of Presentation: 朱鷺メッセ（新潟市）
  • Year and Date: 2014-11-21
• [Presentation] Impurity line spectroscopy during spherical tokamak merging in UTST (2014)
  • Author(s): H. Ishikawa, T. G Watanabe, N. Kawakami and M. Inomoto
  • Organizer: Plasmaconference 2014
  • Place of Presentation: 朱鷺メッセ（新潟市）
  • Year and Date: 2014-11-19
• [Presentation] Study of Electron Acceleration during Magnetic Reconnection in UTST device (2014)
  • Author(s): T. Ushiki, K. Ishiguchi, K. Matsuyama, H. Koguchi, M. Inomoto
  • Organizer: Plasmaconference 2014
  • Place of Presentation: 朱鷺メッセ（新潟市）
  • Year and Date: 2014-11-18
• [Presentation] Evaluation of Electron Heating during Strong Guide-Field Magnetic Reconnection in UTST Merging Experiment (2014)
  • Author(s): X. Guo, T. Sugawara, A. Wang, M. Inomoto, Y. Ono
  • Organizer: Plasmaconference 2014
  • Place of Presentation: 朱鷺メッセ（新潟市）
  • Year and Date: 2014-11-18
• [Presentation] Generation of Energetic Electrons by Magnetic Reconnection with Presence of High Guide Field (2014)
  • Author(s): M. Inomoto, T.G. Watanabe, K. Yamasaki, S. Kamio, T. Yamada, A. Wang, X. Guo, T. Ushiki, H. Ishikawa, H. Nakamata, H. Itagaki, A. Kuwahata, B. Gao, R. Yanai
  • Organizer: 25th IAEA Fusion Energy Conference
  • Place of Presentation: サンクトペテルブルグ（ロシア）
  • Year and Date: 2014-10-13
• [Presentation] Merging startup of high beta spherical tokamak by using outer poloidal field coils (2014)
  • Author(s): M. Inomoto, T.G. Watanabe, K. Yamasaki, A. Wang, T. Ushiki, X. Guo, H. Ishikawa, H. Nakamata, N. Kawakami, T. Sugawara, K. Matsuyama, Y. Ono
  • Organizer: Workshop on Exploratory Topics in Plasma and Fusion Research (EPR) and US-Japan Compact Torus (CT) Workshop
  • Place of Presentation: ウィスコンシン州マディソン（米国）
  • Year and Date: 2014-08-08
• [Presentation] Observation of Energetic Electrons Generated during Guide Field Reconnection (2014)
  • Author(s): M. Inomoto, T.G. Watanabe, K. Yamasaki, A. Wang, T. Ushiki, X. Guo, H. Ishikawa, H. Nakamata, A. Kuwahata, R. Yanai, Y. Ono
  • Organizer: US-Japan Workshop on Magnetic Reconnection MR2014
  • Place of Presentation: 東京大学（東京都文京区）
  • Year and Date: 2014-05-20
  • Invited
• [Remarks] INOMOTO Michiaki's web site
  • URL: http://tanuki.t.u-tokyo.ac.jp/inomoto/