Updated on 2025/03/24

写真a

 
MIYAKE Fusa
 
Organization
Institute for Space-Earth Environmental Research Associate Professor
Graduate School
Graduate School of Science
Title
Associate Professor
Contact information
メールアドレス
External link

Degree 1

  1. 博士(理学) ( 2013.12   名古屋大学 ) 

Research Interests 3

  1. 宇宙線生成核種

  2. 太陽活動

  3. 宇宙線生成核種

Research Areas 1

  1. Natural Science / Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics

Current Research Project and SDGs 1

  1. 宇宙線生成核種を用いた過去の極端太陽現象の調査

Research History 4

  1. Nagoya University   Institute for Space-Earth Environmental Research Division for Cosmic Ray Research   Associate Professor

    2017.4

  2. アリゾナ大学滞在研究員

    2015.1 - 2016.3

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    Country:United States

  3. Institute for Advanced Research (Institute for Space-Earth Environmental Research), Nagoya University   Designated Assistant Professor

    2014.4 - 2017.3

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    Country:Japan

  4. Nagoya University   Institute for Advanced Research   Designated Assistant Professor

    2014.4 - 2017.3

Education 2

  1. Nagoya University   Graduate School, Division of Natural Science

    - 2013.12

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    Country: Japan

  2. Nagoya University   Faculty of Science

    - 2009.3

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    Country: Japan

Professional Memberships 5

  1. 日本物理学会

  2. 日本地球惑星科学連合

  3. 応用物理学会

  4. 日本物理学会

  5. 日本地球惑星科学連合

Committee Memberships 7

  1.   Joint Symposium of Space Climate 9 Symposium and ISEE Symposium, Organizing Committee  

    2024   

  2. 38th International Cosmic Ray Conference (ICRC2023)   International Scientific Program Committee  

    2023   

  3. 38th International Cosmic Ray Conference (ICRC2023)   Local Organizing Comittee  

    2023   

  4. 24th Radiocarbon – 10th 14C & Archaeology international conferences   International Scientific Advisory Board  

    2022   

  5. The 5th ISEE Symposium: Toward the Future of Space–Earth Environmental Research   SOC, LOC  

    2022   

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Awards 5

  1. José A. Boninsegna Frontiers in Dendrochronology Award

    2022.6   Tree-Ring Society  

    Fusa Miyake

  2. 平成29年度 文部科学大臣表彰 若手科学者賞

    2017.4   文部科学省  

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    Country:Japan

  3. 平成29年度 文部科学大臣表彰 若手科学者賞

    2017.4  

    三宅 芙沙

  4. 育志賞

    2014   日本学術振興会  

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    Country:Japan

  5. 名古屋大学学術奨励賞

    2013   名古屋大学  

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    Country:Japan

 

Papers 58

  1. Transient Offset in <sup>14</sup>C After the Carrington Event Recorded by Polar Tree Rings Reviewed Open Access

    Joonas Uusitalo, Kseniia Golubenko, Laura Arppe, Nicolas Brehm, Thomas Hackman, Hisashi Hayakawa, Samuli Helama, Kenichiro Mizohata, Fusa Miyake, Harri Mäkinen, Pekka Nöjd, Eija Tanskanen, Fuyuki Tokanai, Eugene Rozanov, Lukas Wacker, Ilya Usoskin, Markku Oinonen

    Geophysical Research Letters   Vol. 51 ( 5 )   2024.3

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Geophysical Union (AGU)  

    Abstract

    The Carrington event of 1859 has been the strongest solar flare in the observational history. It plays a crucial role in shedding light on the frequency and impacts of the past and future Solar Energetic Particle (SEP) events on human societies. We address the impact of the Carrington event by measuring tree‐ring <sup>14</sup>C with multiple replications from high‐latitude locations around the event and by comparing them with mid‐latitude measurements. A transient offset in <sup>14</sup>C following the event is observed with high statistical significance. Our state‐of‐the‐art <sup>14</sup>C production and transport model does not reproduce the observational finding, suggesting features beyond present understanding. Particularly, our observation would require partially fast transport of <sup>14</sup>C between the stratosphere and troposphere at high latitudes. The observation is consistent with the previous findings with the SEP events of 774 and 993 CE for which faster integration of <sup>14</sup>C into tree rings is observed at high latitudes.

    DOI: 10.1029/2023GL106632

    Open Access

    Web of Science

    Scopus

  2. No signature of extreme solar energetic particle events in high-precision 14C data from the Alaskan tree for 1844–1876 CE Invited Reviewed Open Access

    Fusa Miyake, Masataka Hakozaki, Hisashi Hayakawa, Naruki Nakano, Lukas Wacker

    Journal of Space Weather and Space Climate   Vol. 13   2023.12

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:EDP Sciences  

    Cosmogenic nuclides—14C from tree rings and 10Be &amp; 36Cl from ice cores serve as an effective proxy for past extreme solar energetic particle (SEP) events. After identifying the first signature of an extreme SEP event in 774 CE, several candidates have been found in these proxy archives, such as 993 CE, 660 BCE, and 7176 BCE. Their magnitudes have been estimated to be tens of times larger than that of the largest SEP event ever observed since 1950s. Although a detailed survey of such extreme SEP events is ongoing, the detection of intermediate-sized SEP events that bridge the gap between modern observations and extreme events detected in cosmogenic nuclides has not progressed sufficiently, primarily because of the uncertainties in cosmogenic nuclide data. In this study, we measured 14C concentrations in tree rings in the 19th century (1844–1876 CE) to search for any increases in 14C concentrations corresponding to intermediate-size extreme SEP events. We utilized Alaskan tree-ring samples cut into early and latewoods to suppress the potential seasonal variations in intra-annual 14C data. Notably, no significant 14C variations were observed between early and latewoods (0.0 ± 0.3‰), and the annual resolution 14C data series displayed an error of ~0.8‰. Over the entire study period, no significant increase in 14C concentrations characterized by other candidates of extreme SEP events such as the 774 CE event was detected in the annual 14C data. The present result imposes a constraint on the SEP fluence when the largest-class of recorded solar storms occurred (especially those in 1859 CE and 1872 CE).

    DOI: 10.1051/swsc/2023030

    Open Access

    Web of Science

    Scopus

  3. Extreme Solar Events: Setting up a Paradigm Reviewed Open Access

    Ilya Usoskin, Fusa Miyake, Melanie Baroni, Nicolas Brehm, Silvia Dalla, Hisashi Hayakawa, Hugh Hudson, A. J. Timothy Jull, Delores Knipp, Sergey Koldobskiy, Hiroyuki Maehara, Florian Mekhaldi, Yuta Notsu, Stepan Poluianov, Eugene Rozanov, Alexander Shapiro, Tobias Spiegl, Timofei Sukhodolov, Joonas Uusitalo, Lukas Wacker

    Space Science Reviews   Vol. 219 ( 8 )   2023.12

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    Abstract

    The Sun is magnetically active and often produces eruptive events on different energetic and temporal scales. Until recently, the upper limit of such events was unknown and believed to be roughly represented by direct instrumental observations. However, two types of extreme events were discovered recently: extreme solar energetic particle events on the multi-millennial time scale and super-flares on sun-like stars. Both discoveries imply that the Sun might rarely produce events, called extreme solar events (ESE), whose energy could be orders of magnitude greater than anything we have observed during recent decades. During the years following these discoveries, great progress has been achieved in collecting observational evidence, uncovering new events, making statistical analyses, and developing theoretical modelling. The ESE paradigm lives and is being developed. On the other hand, many outstanding questions still remain open and new ones emerge. Here we present an overview of the current state of the art and the forming paradigm of ESE from different points of view: solar physics, stellar–solar projections, cosmogenic-isotope data, modelling, historical data, as well as terrestrial, technological and societal effects of ESEs. Special focus is paid to open questions and further developments. This review is based on the joint work of the International Space Science Institute (ISSI) team #510 (2020–2022).

    DOI: 10.1007/s11214-023-01018-1

    Open Access

    Web of Science

    Scopus

    Other Link: https://link.springer.com/article/10.1007/s11214-023-01018-1/fulltext.html

  4. Regional Differences in Carbon-14 Data of the 993 CE Cosmic Ray Event Reviewed Open Access

    Fusa Miyake, Masataka Hakozaki, Katsuhiko Kimura, Fuyuki Tokanai, Toshio Nakamura, Mirei Takeyama, Toru Moriya

    Frontiers in Astronomy and Space Sciences   Vol. 9   2022.7

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Frontiers Media SA  

    Cosmogenic nuclides such as <sup>14</sup>C from tree rings and <sup>10</sup>Be and <sup>36</sup>Cl from ice cores are excellent proxies for the past extremely large solar energetic particle (SEP) events, which are dozens of times larger than the largest SEP event in the history of observation. So far, several rapid <sup>14</sup>C increases have been discovered, which are considered to have originated from extreme SEP events (or set of successive SEP events) from verifications using multiple cosmogenic nuclide analyses in natural archives. Although these events are characterized by a rapid increase in cosmogenic nuclide concentrations, <sup>14</sup>C data recorded worldwide do not always show similar variations, especially during the 993 CE event, where a rapid increase was recorded in either 992–993 CE or 993–994 CE in several records. We present new <sup>14</sup>C data of the Japanese cedar sample for the 993 CE event. Although the latest data show no significant increase in 1 year, an overall increase pattern is consistent with the previously reported <sup>14</sup>C data of the Japanese cedar, which supports that a significant <sup>14</sup>C increase occurred from 993 to 994 CE in the Japanese sample. Given the dominant <sup>14</sup>C production in high latitudes by SEPs, the difference in timing of increase may be a transport effect in the atmosphere. Moreover, the difference in the timing of the <sup>14</sup>C increase can cause a 1-year age-determination error using the 993 CE radiocarbon spike. Compared with the <sup>14</sup>C data between tree samples from high latitude and midlatitude, including Japan, high-latitude data can capture <sup>14</sup>C changes originating from SEP events more quickly and clearly and may be more suitable for a SEP event exploration in the past.

    DOI: 10.3389/fspas.2022.886140

    Open Access

    Web of Science

    Scopus

  5. A Single-Year Cosmic Ray Event at 5410 BCE Registered in 14C of Tree Rings. Reviewed International coauthorship International journal Open Access

    F Miyake, I P Panyushkina, A J T Jull, F Adolphi, N Brehm, S Helama, K Kanzawa, T Moriya, R Muscheler, K Nicolussi, M Oinonen, M Salzer, M Takeyama, F Tokanai, L Wacker

    Geophysical research letters   Vol. 48 ( 11 ) page: e2021GL093419   2021.6

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    The annual 14C data in tree rings is an outstanding proxy for uncovering extreme solar energetic particle (SEP) events in the past. Signatures of extreme SEP events have been reported in 774/775 CE, 992/993 CE, and ∼660 BCE. Here, we report another rapid increase of 14C concentration in tree rings from California, Switzerland, and Finland around 5410 BCE. These 14C data series show a significant increase of ∼6‰ in 5411-5410 BCE. The signature of 14C variation is very similar to the confirmed three SEP events and points to an extreme short-term flux of cosmic ray radiation into the atmosphere. The rapid 14C increase in 5411/5410 BCE rings occurred during a period of high solar activity and 60 years after a grand 14C excursion during 5481-5471 BCE. The similarity of our 14C data to previous events suggests that the origin of the 5410 BCE event is an extreme SEP event.

    DOI: 10.1029/2021GL093419

    Web of Science

    Scopus

    PubMed

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Books 6

  1. Extreme Solar Particle Storms: The hostile Sun

    F. Miyake, I. Usoskin, S. Poluianov eds.( Role: Sole author)

    Institute of Physics Publishing  2019.12 

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    Language:Japanese

  2. 環境年表2023-2024

    ( Role: Contributor)

    2023.11  ( ISBN:9784621308448

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    Language:Japanese

  3. 特集推定不能 : 炭素14研究がとらえた未知の巨大太陽フレアの謎

    国立歴史民俗博物館, 箱﨑, 真隆, 橋本, 雄太( Role: Contributor)

    人間文化研究機構国立歴史民俗博物館,文学通信 (発売)  2023.6  ( ISBN:9784867660140

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    Total pages:111p   Language:Japanese

    CiNii Books

  4. 激動の天と地

    日経サイエンス編集部( Role: Supervisor (editorial))

    日経サイエンス,日経BPマーケティング (発売)  2023.2  ( ISBN:9784296116911

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    Total pages:126p   Language:Japanese

    CiNii Books

  5. 特集:スーパーフレア 巨木の年輪に刻まれた太陽の異変 古文書が助けた科学解析

    ( Role: Supervisor (editorial))

    日経サイエンス  2022.4 

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    Language:Japanese

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MISC 32

  1. Exploring past extreme solar energetic particle events from the Antarctic Dome Fuji Ice

    Fusa Miyake, Naoyuki Kurita, Kazuho Horiuchi, Sumito Matoba, Hiroyuki Matsuzaki, Takeyasu Yamagata

        2024

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    Authorship:Lead author, Corresponding author  

  2. Investigation of extreme solar energetic particle events in the 19th century by tree-ring <sup>14</sup>C analysis

    三宅芙沙, 箱崎真隆, 早川尚志, WACKER Lukas

    日本物理学会講演概要集(CD-ROM)   Vol. 79 ( 1 )   2024

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  3. 極端宇宙天気と炭素14 : 過去1万年間の太陽活動—特集 推定不能 : 炭素14研究がとらえた未知の巨大太陽フレアの謎 Invited

    三宅 芙沙

    Rekihaku / 国立歴史民俗博物館 編   Vol. 9   page: 22 - 28   2023.6

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    Authorship:Lead author, Corresponding author   Language:Japanese   Publisher:人間文化研究機構国立歴史民俗博物館  

  4. Investigation of past extreme solar events by radiocarbon analyses Invited

    Miyake Fusa

    Journal of the Atomic Energy Society of Japan   Vol. 65 ( 2 ) page: 104 - 107   2023

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    Authorship:Lead author, Corresponding author   Language:Japanese   Publisher:Atomic Energy Society of Japan  

    DOI: 10.3327/jaesjb.65.2_104

    CiNii Research

    J-GLOBAL

  5. Investigation of solar activities in the 19<sup>th</sup> century by <sup>14</sup>C analyses of tree rings

    三宅芙沙, 箱崎真隆, 早川尚志, WACKER Lukas

    応用物理学会春季学術講演会講演予稿集(CD-ROM)   Vol. 70th   2023

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Presentations 24

  1. 樹木年輪の炭素14濃度に刻まれた過去の宇宙線増加現象 Invited

    三宅 芙沙

    第79回応用物理学会 秋季学術講演会  2018.9 

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    Language:Japanese   Presentation type:Oral presentation (invited, special)  

  2. 樹木年輪から探る過去の大規模SPE Invited

    三宅 芙沙

    SGEPSS  2018.11 

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    Language:Japanese   Presentation type:Oral presentation (invited, special)  

  3. Rapid cosmic ray events shown in carbon-14 data of tree rings Invited International conference

    F. Miyake

    PSTEP A04 International Workshop  2019.2 

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    Language:English   Presentation type:Oral presentation (invited, special)  

  4. Cosmogenic Evidences for Past SEP Events Invited International conference

    F. Miyake

    36th International Cosmic Ray Conference, Madison  2019.7 

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    Language:English   Presentation type:Oral presentation (keynote)  

  5. Annual cosmic ray events shown in carbon-14 data from the BC 10th to AD 14th century International conference

    F. Miyake

    23rd Radiocarbon conference  2018.6 

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    Language:English   Presentation type:Oral presentation (keynote)  

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Research Project for Joint Research, Competitive Funding, etc. 1

  1. 宇宙線生成核種による過去数万年の宇宙線大変動探索計画

    2014.9 - 2016

KAKENHI (Grants-in-Aid for Scientific Research) 16

  1. 水月湖年縞堆積物による過去の太陽スーパーフレアの研究

    Grant number:23K17694  2023.6 - 2025.3

    日本学術振興会  科学研究費助成事業  挑戦的研究(萌芽)

    三宅 芙沙, 中川 毅, 林田 明, 柴田 一成, 中川 毅, 林田 明, 柴田 一成

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    Authorship:Principal investigator 

    Grant amount:\6370000 ( Direct Cost: \4900000 、 Indirect Cost:\1470000 )

    太陽で巨大なフレアが発生すると、その影響が地球へ伝わり、人工衛星故障、通信障害、停電などの被害が発生することが知られている。現代社会の発展、とくに宇宙への進出に伴って、太陽ではどこまで巨大なフレアが発生するのか、世界的な関心が高まりつつある。本研究は、福井県若狭湾沿岸にある水月湖の堆積物中の放射性炭素の分析から、過去の太陽における超巨大フレア(スーパーフレア)の探索を行う。本挑戦的研究が成功すれば、将来的には5万年間の太陽スーパーフレアの歴史や統計的法則、さらには、太陽活動の変遷が判明する道が開かれると期待される。
    太陽で巨大なフレアが発生すると、その影響が地球へ伝わり、人工衛星故障、通信障害、停電などの被害が発生することが知られている。現代社会の発展、とくに宇宙への進出に伴って、太陽ではどこまで巨大なフレアが発生するのか、世界的な関心が高まっている。このような背景のもと、樹木年輪の炭素14分析から過去のスーパーフレア探索が世界中で進められているが、樹木年輪が利用できるのは主にこの完新世に限定され、それを上回る年代の調査が難しい。それに対して、福井県若狭湾沿岸にある三方五湖の一つ水月湖の湖底には、7万年におよぶ年縞堆積物が残されている。本研究は、水月湖堆積物の花粉を用いた炭素14分析から、774~775年の宇宙線イベントを起こしたと考えられるスーパーフレアの証拠再現が可能かどうか検証する。本挑戦的研究が成功すれば、水月湖堆積物を用いた、過去約5万年間のスーパーフレア探索が可能となる。
    本年度は、774~775年周辺の水月湖堆積物コアの選定を行った。既存の水月湖の低時間分解能な炭素14データから、774年付近は±34年(2σ)で年代決定されているため、この年代周辺を±8試料ずつ計16試料(つまり約100年分)分析できるよう試料の準備を進めた。まずは、用意した試料の両端の炭素14分析を行うように前処理を実施した。堆積物の花粉の抽出には、立命館大学が堆積物の花粉化石の抽出技術の開発を行った「セルソーター」装置を使用した。堆積物試料の前処理~炭素14分析は、立命館大学による商業サービスの「花粉抽出+炭素14測定」パッケージを利用し、今後順次14C測定を進める。
    既に試料の選定を終え、前処理を順次進めている。現在、東京大学博物館の加速器質量分析装置に前処理済みの試料を送付しており、今後早い段階で炭素14の分析結果を得られると考えられる。
    現在測定を待っている両端試料の炭素14測定結果が得られたら、炭素14年代を確認する。両端試料の年代が問題ないことを確認した後、準備している試料の前処理、炭素14分析を順次進め、774/775年の炭素14スパイクがみられるか確認する。

  2. マルチスケール宇宙線生成核種分析より紐解く地質時代の宇宙・地球現象と環境変動

    Grant number:23H00135  2023.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(A)

    堀内 一穂, 宮原 ひろ子, 三宅 芙沙, 川村 賢二, 大藪 幾美, 山崎 俊嗣, 小田 啓邦, 笹 公和, 宮原 ひろ子, 三宅 芙沙, 川村 賢二, 大藪 幾美, 山崎 俊嗣, 小田 啓邦, 笹 公和

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    Authorship:Coinvestigator(s) 

    太陽地磁気変動や宇宙線イベントなどに由来する宇宙・地球現象は、地球惑星科学の主要な研究対象の一つであり、近年では災害科学の観点からも注目されている。しかし、地質時代のそれを知る手段は相当に限られる。本研究では、宇宙線と大気との相互作用により生成する宇宙線生成核種を様々な時空間スケールで戦略的に分析することで、過去400万年間の宇宙・地球現象を、連続的もしくは注目する区間で集中的に解明する。またその応用として、アイスコア・堆積物・年輪などの古環境アーカイブから獲得される宇宙線生成核種記録の層序学的利用を推進させるとともに、環境トレーサー・プロキシとしての宇宙線生成核種の利用も開拓する。
    東太平洋赤道域のIODP Site U1335にて掘削されたコア試料について、80万年前から185万年前の1万年解像度ベリリウム同位体記録を獲得し、この時代に頻発した地磁気逆転やエクスカーションに伴うベリリウム10の増大を検出した。また、南極ドームふじアイスコアを対象に、酸素同位体ステージ7の百年解像度ベリリウム10分析を開始するとともに、年代モデル向上のための気体分析を行った。さらに、西太平洋やインド洋の海底堆積物を対象に、過去数十万年間の散点的なベリリウム同位体分析を行った。
    最終間氷期(約13万年前)のドームふじアイスコアを対象に、年解像度のベリリウム10分析を約百年間行った結果、シュワーベ周期に対応する明瞭な周期性が見出された。また、19万年前の地磁気極小期にて既に得られている500年分の約2年解像度のベリリウム10データに関して、時系列解析を進めた。これらは地質時代の太陽活動を解明するための貴重なデータであり、特に前者について今後さらに期間を拡張して分析を継続する予定である。
    完新世の宇宙線イベントや太陽活動に関して、アイスコアやトラバーチンを対象に、季節から単年解像度のベリリウム10分析を行い、年輪炭素14分析の結果とともに解析を進めた。具体的には、南北両極沿岸アイスコアや内陸トレンチ試料のベリリウム10分析を行った。また19世紀の宇宙線イベントを対象にした年輪炭素14分析結果の公表や、グリーンランド南東ドームアイスコアの詳細年代の公表により、今後行われる19世紀のベリリウム10詳細分析に備えた。さらに、1510年から1701年のトラバーチン単年ベリリウム10記録を公表した。
    以上の結果に基づいて、古地磁気強度変動を加味しながら、得られた記録間の宇宙線変動対比を行った。また、宇宙線変動と気候環境との関係を考察した。
    本事業は大きく分けて、(1)過去400万年間を単独で網羅する1万年解像度のベリリウム10記録の獲得、(2)過去数十万年間を網羅する複数の百年解像度ベリリウム10記録の獲得、(3)既知および新たに発見された宇宙線イベントを対象にした季節から単年解像度の宇宙線生成核種記録の獲得、(4)上記記録間の同期・比較・解析と地質時代の太陽地磁気変動史や宇宙線イベントの同定・解明、(5)宇宙線変動記録の精密化と新たな古環境プロキシの開拓を目標としている。記録の獲得(1-3)はぼぼ計画通りに進んでおり、応用(4-5)への取り組みも始まっていることから、計画はおおむね順調に進展していると判断できる。
    計画の遂行に大きな問題は生じていないことから、当初の計画通り課題を推進する予定である。

  3. Development in the resolution of age calibration of the Yayoi to Kofu periods by high-precision 14C measurements of annual tree rings.

    Grant number:22H00026  2022.4 - 2027.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Authorship:Coinvestigator(s) 

  4. Solar activity over the past 10,000 years

    Grant number:20H05643  2020.8 - 2025.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (S)

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\198120000 ( Direct Cost: \152400000 、 Indirect Cost:\45720000 )

  5. Establishment of a method for detecting Schwabe cycles using cosmogenic nuclides

    Grant number:20K20918  2020.7 - 2023.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    Miyake Fusa

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\6370000 ( Direct Cost: \4900000 、 Indirect Cost:\1470000 )

    Radiocarbon in tree rings is an excellent proxy for solar magnetic activities. However, a method for detecting the 11-year solar cycle (Schwabe cycle) using 14C has not been established. To investigate seasonal variations within annual tree-ring layers that may prevent the detection of the Schwabe cycle, we measured 14C concentrations in early and latewoods of tree samples from multiple locations. The results showed that the magnitude of 14C variations within annual layers differs depending on the tree species or locations, and it is important to correctly understand the seasonal variations of trees using for the analysis. We conducted multiple measurements for the same year using tree samples in which seasonal variations could not be confirmed with high accuracy for the period from 1844 to 1876 CE. We observed cyclic variations in measured 14C data which are consistent with the Schwabe cycle presumed from a sunspot record.

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Teaching Experience (On-campus) 7

  1. Paleo Cosmic Ray Physics

    2020

  2. 物理学実験I

    2020

  3. 物理学実験II

    2020

  4. Cosmic-ray Physics Seminar 4

    2020

  5. 地球学

    2020

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Social Contribution 35

  1. 中日文化センター 巨大太陽フレアと地球環境

    Role(s):Lecturer

    2018.3

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    Audience: Junior students, High school students, College students, Graduate students, Teachers, Guardians, General

    Type:Lecture

  2. 麗澤瑞浪 中学・高等学校 研究室紹介

    Role(s):Lecturer

    2017.11

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    Audience: Junior students, High school students

    Type:Other

  3. わかりやすい科学 「科学のたまご」を君のこころに 科学講座

    2017.2

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    Audience: Schoolchildren, Guardians

    Type:Lecture

  4. 小・中学生向け夏休み体験学習「樹木年輪・年縞堆積物から過去の太陽活動、地球の古気候を探る」

    Role(s):Lecturer

    2016.8

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    Audience: Schoolchildren, Junior students

    Type:Lecture

  5. 名古屋大学宇宙地球環境研究所公開講演会「嵐を測る」

    Role(s):Lecturer

    2016.7

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    Audience: General

    Type:Lecture

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Media Coverage 11

  1. Hiukkasmyrskyt jättävät jäljen puiden vuosi­renkaisiin/太陽粒子嵐が年輪に痕跡を残す(訳) Newspaper, magazine

    Helsingin Sanomat  2023.9

  2. MARKING TIME Newspaper, magazine

    Science, Vol 380, Issue 6641  doi: 10.1126/science.adi2040  2023.4

  3. Seven technologies to watch in 2023 Newspaper, magazine

    Nature  https://doi.org/10.1038/d41586-023-00178-y  2023.1

  4. Solar ‘Superflares’ Rocked Earth Less Than 10,000 Years Ago—and Could Strike Again Newspaper, magazine

    Scientific American Magazine Vol. 325 No. 6  2021.12

  5. Vikings Were in the Americas Exactly 1,000 Years Ago Newspaper, magazine

    The New York times  2021.10

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