あらせ衛星観測とシミュレーションによる放射線帯電子の非線形加速・散乱過程の理解

2022 Fiscal Year Annual Research Report

• Project/Area Number: 20H01959
• Research Institution: Nagoya University
• Principal Investigator: 三好 由純 名古屋大学, 宇宙地球環境研究所, 教授 (10377781)
• Co-Investigator(Kenkyū-buntansha): 松田 昇也 金沢大学, 電子情報通信学系, 准教授 (20772213) ; 加藤 雄人 東北大学, 理学研究科, 教授 (60378982) ; 齊藤 慎司 国立研究開発法人情報通信研究機構, 電磁波研究所電磁波伝搬研究センター, 主任研究員 (60528165) ; 栗田 怜 京都大学, 生存圏研究所, 准教授 (90785495)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 放射線帯 / 数値シミュレーション / あらせ衛星 / 波動粒子相互作用

Outline of Annual Research Achievements

地球周辺の高度1,000 kmから40,000 km付近の宇宙空間には、放射線帯（ヴァン・アレン帯）と呼ばれる高いエネルギーを持つ荷電粒子群が存在する。放射線帯に存在する電子群は、太陽からのプラズマ流（太陽風）の変化に応じて、その数が大きく増減する。「あらせ」衛星などによる新しい観測によって、非線形のプラズマ波動が電子の散乱や加速を引き起こし、放射線帯の電子の数が変化している様子が観測されてきた。しかし、衛星の観測データは衛星周辺の様子のみを計測するため、プラズマ波動が放射線帯の電子群全体に及ぼす影響はわかっていない。本年度の研究では、これまで提案した低周波数コーラス(LBC)による非線形波動粒子相互作用のモデル(Miyoshi et al., 2020)にもとづく数keVの電子が起こす脈動オーロラとMeVを超える相対論的電子バーストの同一性に関する検証を進めた。特に、このモデルが予言する降下電子の逆エネルギー分散構造について、観測ロケット(Namekawa, Miyoshi et al., 2023)や人工衛星観測（Shumko, Miyoshi et al., 2023)から得られたエネルギー分散構造とモデルにもとづくシミュレーションとの比較を行い、シミュレーションと観測データとがきわめてよい整合性を示すことが明らかになり、学術論文として報告した。この逆エネルギー分散構造は、従来のモデルでは説明できず、研究代表者らが提案したLBCが磁力線に沿って伝搬しながら異なるエネルギーの電子を散乱させるというモデルに特徴的なものである。上記の逆エネルギー分散構造の同定によって、本モデルの妥当性が実証され、相対論的電子バーストが脈動オーロラに付随して起こるという新しい描像がが明らかになった。

Research Progress Status

令和4年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和4年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] ロスアラモス国立研究所/アラスカ大学/NASA(米国)
  • Country Name: U.S.A.
  • Counterpart Institution: ロスアラモス国立研究所/アラスカ大学/NASA
  • # of Other Institutions: 1
• [Journal Article] The RAM-SCB model and its applications to advance space weather forecasting (2023)
  • Author(s): Jordanova V.K.、Morley S.K.、Engel M.A.、Godinez H.C.、Yakymenko K.、Henderson M.G.、Yu Y.、Miyoshi Y.
  • Journal Title: Advances in Space Research Volume: 72 Pages: 5596～5606
  • DOI: 10.1016/j.asr.2022.08.077
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Whistler‐Mode Transmission Experiments in the Radiation Belts: DSX TNT Circuit Simulation and Data Analysis (2023)
  • Author(s): Tu Jiannan、Song Paul、Galkin Ivan A.、Reinisch Bodo W.、Johnston William R.、Starks Michael J.、Su Yi‐Jiun、Cooke David、Ginet Gregory P.、Inan Umran S.、Lauben David S.、Miyoshi Yoshizumi、Matsuda Shoya、Kasahara Yoshiya、Kojima Hirotsugu、Shinohara Iku
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2022JA030564
  • DOI: 10.1029/2022JA030564
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Multi‐Event Analysis of Magnetosphere‐Ionosphere Coupling of Nighttime Medium‐Scale Traveling Ionospheric Disturbances From the Ground and the Arase Satellite (2023)
  • Author(s): Kawai K.、Shiokawa K.、Otsuka Y.、Oyama S.、Connors M. G.、Kasahara Y.、Kasaba Y.、Nakamura S.、Tsuchiya F.、Kumamoto A.、Shinbori A.、Matsuoka A.、Shinohara I.、Miyoshi Y.
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2022JA030542
  • DOI: 10.1029/2022JA030542
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Ionospheric Modulation by EMIC Wave‐Driven Proton Precipitation: Observations and Simulations (2023)
  • Author(s): Tian Xingbin、Yu Yiqun、Gong Fan、Ma Longxing、Cao Jinbin、Solomon Stanley C.、Shreedevi P. R.、Shiokawa Kazuo、Otsuka Yuichi、Oyama Shin‐ichiro、Miyoshi Yoshizumi
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2022JA030983
  • DOI: 10.1029/2022JA030983
  • Peer Reviewed
• [Journal Article] Latitudinal dependence of ground VLF transmitter wave power in the inner magnetosphere (2023)
  • Author(s): Xia Zhiyang、Chen Lunjin、Gu Wenyao、Horne Richard B.、Miyoshi Yoshizumi、Kasahara Yoshiya、Kumamoto Atsushi、Tsuchiya Fuminori、Nakamura Satoko、Kitahara Masahiro、Shinohara Iku
  • Journal Title: Frontiers in Astronomy and Space Sciences Volume: 10 Pages: -
  • DOI: 10.3389/fspas.2023.1135509
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Direct Observations of Energetic Electron Scattering and Precipitation Due To Whistler‐Mode Waves in the Dayside High‐Density Regions (2023)
  • Author(s): Sugo Shin、Kasahara Satoshi、Miyoshi Yoshizumi、Katoh Yuto、Keika Kunihiro、Yokota Shoichiro、Hori Tomoaki、Kasahara Yoshiya、Matsuda Shoya、Matsuoka Ayako、Shinohara Iku、Tsuchiya Fuminori、Kumamoto Atsushi、Nakamura Satoko、Kitahara Masahiro
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2022JA030992
  • DOI: 10.1029/2022JA030992
  • Peer Reviewed
• [Journal Article] Using Van Allen Probes and Arase Observations to Develop an Empirical Plasma Density Model in the Inner Zone (2023)
  • Author(s): Hartley D. P.、Cunningham G. S.、Ripoll J.‐F.、Malaspina D. M.、Kasahara Y.、Miyoshi Y.、Matsuda S.、Nakamura S.、Tsuchiya F.、Kitahara M.、Kumamoto A.、Shinohara I.、Matsuoka A.
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2022JA031012
  • DOI: 10.1029/2022JA031012
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Observation of an Electron Microburst With an Inverse Time‐Of‐Flight Energy Dispersion (2023)
  • Author(s): Shumko M.、Miyoshi Y.、Blum L. W.、Halford A. J.、Breneman A. W.、Johnson A. T.、Sample J. G.、Klumpar D. M.、Spence H. E.
  • Journal Title: Geophysical Research Letters Volume: 50 Pages: e2023GL104804
  • DOI: 10.1029/2023GL104804
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Spatio‐Temporal Characteristics of IPDP‐Type EMIC Waves on April 19, 2017: Implications for Loss of Relativistic Electrons in the Outer Belt (2023)
  • Author(s): Hirai Asuka、Tsuchiya Fuminori、Obara Takahiro、Katoh Yuto、Miyoshi Yoshizumi、Shiokawa Kazuo、Kasaba Yasumasa、Misawa Hiroaki、Jun Chae‐Woo、Kurita Satoshi、Connors Martin G.、Hendry Aaron T.、Shinbori Atsuki、Otsuka Yuichi、Tsugawa Takuya、Nishioka Michi、Perwitasari Septi、Manweiler Jerry W.
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2023JA031479
  • DOI: 10.1029/2023JA031479
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The variable source of the plasma sheet during a geomagnetic storm (2023)
  • Author(s): Kistler L. M.、Asamura K.、Kasahara S.、Miyoshi Y.、Mouikis C. G.、Keika K.、Petrinec S. M.、Stevens M. L.、Hori T.、Yokota S.、Shinohara I.
  • Journal Title: Nature Communications Volume: 14 Pages: -
  • DOI: 10.1038/s41467-023-41735-3
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Simultaneous Precipitation of Sub‐Relativistic Electron Microburst and Pulsating Aurora Electrons (2023)
  • Author(s): Namekawa T.、Mitani T.、Asamura K.、Miyoshi Y.、Hosokawa K.、Lessard M.、Moser C.、Halford A. J.、Sakanoi T.、Kawamura M.、Nose M.、Nomura R.、Teramoto M.、Shumko M.、Lynch K. A.、Jaynes A. N.、McHarg M. G.
  • Journal Title: Geophysical Research Letters Volume: 50 Pages: e2023GL104001
  • DOI: 10.1029/2023GL104001
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Observation of Whistler Mode Waves Inside Mirror Mode Structures in the Earth's Outer Magnetosphere (2023)
  • Author(s): Chen Rui、Gao Xinliang、Lu Quanming、Tsurutani Bruce T.、Miyoshi Yoshizumi、Zhou Xuan、Ke Yangguang、Chen Huayue、Ma Jiuqi
  • Journal Title: Journal of Geophysical Research: Space Physics Volume: 128 Pages: e2023JA031792.
  • DOI: 10.1029/2023JA031792
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Space Radiation (2023)
  • Author(s): Miyoshi Yoshizumi、Katoh Yuto、Saito Shinji、Mitani Takefumi、Takashima Takeshi
  • Journal Title: Solar-Terrestrial Environmental Prediction Volume: - Pages: 115～137
  • DOI: 10.1007/978-981-19-7765-7_5
  • Peer Reviewed
• [Presentation] Code coupling simulation of whistler mode chorus waves during storm time (2023)
  • Author(s): Yoshizumi Miyoshi, Vania Jordanova , Yuto Katoh, Shinji Saito, Satoshi Kurita, Shoya Matsuda , Shreedevi P.R.
  • Organizer: URSI-GASS2023
  • Int'l Joint Research
• [Presentation] Multiple roles of plasma waves in Geospace (2023)
  • Author(s): Yoshizumi Miyoshi
  • Organizer: URSI-GASS2023
  • Int'l Joint Research / Invited
• [Presentation] Evolution of energy spectrum during electron accelerations in the outer radiation belt (2023)
  • Author(s): Y. Miyoshi, S, Saito, S. Kurita, S. Matsuda, Y. Katoh, R. Kataoka, S. Imajo, T. Hori, S. Nakamura, T. Mitani, I. Shinohara, T. Takashima, N. Higashio, S. Kasahara, S. Yokota, K. Keika, K. Asamura, A. Matsuoka, F. Tsuchiya, A. Kumamoto, and Y. Kasahara
  • Organizer: SGEPSS
• [Presentation] In-situ observations of plasma/particle distribution function and plasma waves by the Arase satellite (2023)
  • Author(s): Y. Miyoshi, K. Asamura, Y. Kazama, S. Saito, S. Kurita, S. Matsuda, Y. Katoh, S. Imajo, M. Shoji, T. Hori, C-W. Jun, S. Nakamaura, S.-Y. Wang, S. Kasahara, S. Yokota, T. Mitani, N. Higashio, Y. Kasahara, H. Kojima, A. M
  • Organizer: 7th Asia-Pacific Conference on Plasma Physics
  • Int'l Joint Research / Invited
• [Presentation] Activities of low-frequency plasma waves in the dayside magnetospehre observed by the Arase satellite (2023)
  • Author(s): Y. Miyoshi, C-W. Jun, R. Chen, Y. Kasahara, S. Matsuda, K. Asamura, T. Hori, S. Nakamura, S. Kurita, Y. Katoh, I. Shinohara, S. Kasahara, S. Yokota, K. Keika, T. Mitani, T. Takashima, N. Higashio, F. Tsuchiya, A. Kumamoto, and A. Matsuoka
  • Organizer: AGU fall meeting 2023
  • Int'l Joint Research / Invited
• [Presentation] Energetic electron precipitation associated with pulsating aurora (2023)
  • Author(s): Y. Miyoshi, K. Hosokawa, S. Saito, Y. Obayashi, Y. Ogawa, S-I. Oyama, S. Kurita, K. Asamura, P. T. Verronen, A. Kero, E. Turunen, Y. Kazama, S. Kasahara, S. Yokota, T. Mitani, T. Takashima, I. Shinohara, N. Higashio, T. Hori, C-W. Jun,
  • Organizer: AGU fall meeting 2023
  • Int'l Joint Research / Invited