研究者業績

清水 敏文

シミズ トシフミ  (Toshifumi Shimizu)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 教授
(兼任)宇宙科学研究所 高感度太陽紫外線分光観測衛星(SOLAR-C)プリプロジェクトチーム長
東京大学 教授(委)
学位
博士(理学)(1995年3月 東京大学)

J-GLOBAL ID
200901047809298943
researchmap会員ID
0000202790

太陽活動やコロナ加熱問題など、私たちの母なる星「太陽」およびその関連テーマに関して、人工衛星等の飛翔体による観測手段を用いて研究を行っています。2006年から軌道上で運用を続ける「ひので」(SOLAR-B)、観測ロケットや大気球、そして2020年代中盤に飛翔させる公募型小型4号機 SOLAR-Cによる先進的観測実現を可能にする搭載機器や衛星システムの開発にも取り組んでいます。SOLAR-Cには、世界初となる高分解能・高感度のEUV分光望遠鏡EUVSTを搭載します。

 


経歴

 2

主要な論文

 218
  • Mayu Koyama, Toshifumi Shimizu
    The Astrophysical Journal 965(2) 136-11page 2024年4月  査読有り最終著者責任著者
  • 鄭, 祥子, 長谷川, 隆祥, 藤島, 早織, 合田, 雄哉, 村尾, 一, 吉田, 南, 清水, 敏文, 久保, 雅仁, 津野, 克彦
    JAXA-RR-23-002, ページ数 26, 発行日 2024-02-13 2024年2月  査読有り
  • Minami Yoshida, Toshifumi Shimizu, Shin Toriumi
    The Astrophysical Journal 2023年6月1日  
  • Takahiro Hasegawa, Toshifumi Shimizu
    The Astrophysical Journal 943(2) 96-96 2023年1月27日  査読有り
    Abstract Magnetic helicity is a physical parameter used to quantify the complexity of magnetic fields, providing an indication of the energy state in the coronal magnetic structure. We investigate the temporal evolution of magnetic helicity and its relationship to the occurrence of a variety of flares in the solar active region NOAA 12297, which was well observed using the Solar Dynamics Observatory/Helioseismic and Magnetic Imager in 2015 March. The active region produced many M-class flares and an X-class flare in two distinctive areas, both of which had a similar magnetic evolution, i.e., the opposite polarity of an emerging flux developed beside a preexisting sunspot, but exhibited flares with different magnitudes and frequencies. We derived the spatiotemporal evolution of the magnetic helicity injections and evaluated how spinning and braiding helicity injections evolved with time in the two areas. In one area, we observed a remarkable evolution, in which a negative spinning helicity injection in the preexisting sunspot increased in a positive helicity system, followed by the occurrence of the X-class flare. The negative helicity injection was clearly caused by the flux emergence that developed along the outer edge of the preexisting sunspot. The other area showed positive braiding helicity injections, with spinning helicity injections fluctuating concurrently with flux emergence, changing their signs several times, i.e., variable energy, and helicity input. The observed temporal behaviors of the helicity injections may explain different types of flare occurrences in the regions.
  • Takayoshi Oba, Toshifumi Shimizu, Yukio Katsukawa, Masahito Kubo, Yusuke Kawabata, Hirohisa Hara, Fumihiro Uraguchi, Toshihiro Tsuzuki, Tomonori Tamura, Kazuya Shinoda, Kazuhide Kodeki, Kazuhiko Fukushima, José Miguel Morales Fernández, Antonio Sánchez Gómez, María Balaguer Jimenéz, David Hernández Expósito, Achim Gandorfer
    Solar Physics 297(9) 2022年9月  査読有り
    We developed a scan mirror mechanism (SMM) that enable a slit-based spectrometer or spectropolarimeter to precisely and quickly map an astronomical object. The SMM, designed to be installed in the optical path preceding the entrance slit, tilts a folding mirror and then moves the reflected image laterally on the slit plane, thereby feeding a different one-dimensional image to be dispersed by the spectroscopic equipment. In general, the SMM is required to scan quickly and broadly while precisely placing the slit position across the field-of-view (FOV). These performances are in high demand for near-future observations, such as studies on the magnetohydrodynamics of the photosphere and the chromosphere. Our SMM implements a closed-loop control system by installing electromagnetic actuators and gap-based capacitance sensors. Our optical test measurements confirmed that the SMM fulfills the following performance criteria: i) supreme scan-step uniformity (linearity of 0.08%) across the wide scan range (± 1005 ″), ii) high stability (3 σ= 0.1 ″), where the angles are expressed in mechanical angle, and iii) fast stepping speed (26 ms). The excellent capability of the SMM will be demonstrated soon in actual use by installing the mechanism for a near-infrared spectropolarimeter onboard the balloon-borne solar observatory for the third launch, Sunrise III.
  • Masashi Abe, Toshifumi Shimizu, Masumi Shimojo
    Frontiers in Astronomy and Space Sciences 9 908249 2022年6月13日  査読有り
    Nanoflares and the shock formation of magnetohydrodynamic waves in the solar chromosphere have been considered as key physical mechanisms of the heating of the chromosphere and corona. To investigate candidates of their signature in the mm-wavelength, a tiny active region located on the solar disk was observed with the Atacama Large millimeter and sub-millimeter Array (ALMA) at 3 mm, coordinated with observatories on orbit including Hinode SOT spectro-polarimeter in the Cycle 4 solar campaign (19 March 2017). ALMA’s spatial resolution was moderate, far from the best performance, but it provided stable conditions that are suitable to investigate temporal variations in the mm-wavelength. We determined that the noise level is less than 20 K (σ) over 1 hour in the 20-s cadence time series of synthesized ALMA images. The time variations with amplitudes above the noise level were observed throughout the field of view, but variations exceeding 200 K, corresponding to energy input to the chromosphere on the order of 1020-22 erg, were localized in two locations. One location was on the polarity inversion line, where tiny concentrated magnetic patches exist in weak field and a tiny magnetic flux may be emergent. The other location was at the outer edge of a bipolar magnetic region, which was under development with a successive series of magnetic flux emergence. This observation suggests that nanoflare-class energy inputs in the chromosphere can occur associated with emerging flux activities.
  • Toshifumi Shimizu, Masumi Shimojo, Masashi Abe
    The Astrophysical Journal 2021年12月1日  査読有り筆頭著者責任著者
  • 大場崇義, 清水敏文, 勝川行雄, 久保雅仁, 田村友範, 篠田一也, 納富良文, 浦口史寛, 都築俊宏, 原弘久, 小出来一秀, Sami K. SOLANKI, Jose Carlos del, TORO INIESTA
    JAXA-RR-20-009 大気球研究報告 (20-009) 83-89 2021年2月26日  査読有り
  • Shimizu Toshifumi, Imada Shinsuke, Kawate Tomoko, Suematsu Yoshinori, Hara Hirohisa, Tsuzuki Toshihiro, Katsukawa Yukio, Kubo Masahito, Ishikawa Ryoko, Watanabe Tetsuya, Toriumi Shin, Ichimoto Kiyoshi, Nagata Shin’ichi, Hasegawa Takahiro, Yokoyama Takaaki, Watanabe Kyoko, Tsuno Katsuhiko, Korendyke Clarence M., Warren Harry, De Pontieu Bart, Boerner Paul, Solanki Sami K., Teriaca Luca, Schuehle Udo, Matthews Sarah, Long David, Thomas William, Hancock Barry, Reid Hamish, Fludra Andrzej, Auchere Frederic, Andretta Vincenzo, Naletto Giampiero, Poletto Luca, Harra Louise
    Proceedings of SPIE 11444 114440N 2020年12月13日  筆頭著者責任著者
  • Takahiro Hasegawa, Carlos Quintero Noda, Toshifumi Shimizu, Mats Carlsson
    The Astrophysical Journal 900(1) 34-34 2020年8月28日  査読有り
  • Yusuke Kawabata, Andrés Asensio Ramos, Satoshi Inoue, Toshifumi Shimizu
    The Astrophysical Journal 898(1) 32-32 2020年7月20日  査読有り最終著者
  • Y. Kawabata, S. Inoue, T. Shimizu
    The Astrophysical Journal 895(2) 105-105 2020年6月2日  査読有り最終著者
  • T. Oba, Y. Iida, T. Shimizu
    The Astrophysical Journal 890(2) 141-141 2020年2月21日  査読有り最終著者
  • Hinode Review Team, Al-Janabi, Khalid, Antolin, Patrick, Baker, Deborah, Bellot Rubio, Luis R, Bradley, Louisa, Brooks, David H, Centeno, Rebecca, Culhane, J. Leonard, Del Zanna, Giulio, Doschek, George A, Fletcher, Lyndsay, Hara, Hirohisa, Harra, Louise K, Hillier, Andrew S, Imada, Shinsuke, Klimchuk, James A, Mariska, John T, Pereira, Tiago M. D, Reeves, Katharine K, Sakao, Taro, Sakurai, Takashi, Shimizu, Toshifumi, Shimojo, Masumi, Shiota, Daikou, Solanki, Sami K, Sterling, Alphonse C, Su, Yingna, Suematsu, Yoshinori, Tarbell, Theodore D, Tiwari, Sanjiv K, Toriumi, Shin, Ugarte-Urra, Ignacio, Warren, Harry P, Watanabe, Tetsuya, Young, Peter R
    Publications of the Astronomical Society of Japan, 71(5) R1 2019年10月  査読有り
  • Toshifumi Shimizu, Shinsuke Imada, Tomoko Kawate, Kiyoshi Ichimoto, Yoshinori Suematsu, Hirohisa Hara, Yukio Katsukawa, Masahito Kubo, Shin Toriumi, Tetsuya Watanabe, Takaaki Yokoyama, Clarence M. Korendyke, Harry P. Warren, Ted D. Tarbell, Bart De Pontieu, Luca Teriaca, Udo H. Schühle, Sami K. Solanki, Louise K. Harra, Sarah A. Matthews, Andrzej Fludra, Frédéric Auchère, Vincenzo Andretta, Giampiero Naletto, Andrei N. Zhukov
    Proc. SPIE: UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI 11118 1111807 2019年9月9日  筆頭著者責任著者

MISC

 67

書籍等出版物

 5

主要な講演・口頭発表等

 34
  • 清水敏文, 原弘久, 今田晋亮, 他国際 SOLAR-C チーム
    日本天文学会2023年春季年会 2023年3月15日
  • 清水敏文, 原弘久, 今田晋亮, 他国際 Solar-C(EUVST) チーム
    日本天文学会2022年春季年会
  • 清水敏文, 今田晋亮, 原弘久, 末松芳法, 都築俊宏, 勝川行雄, 久保雅仁, 石川遼子, 渡邊鉄哉, 川手朋子, 鳥海森, 鄭祥子, 松崎恵一, 横山央明, 一本潔, 永田伸一, 浅井歩, 草野完也, 渡邉恭子, 飯田佑輔, 他国際 Solar-C(EUVST)チーム
    日本天文学会2021年春季年会
  • 清水 敏文, 鳥海 森, 鄭 祥子, 備後 博生, 原 弘久, 末松 芳法, 勝川 行雄, 久保 雅仁, 石川 遼子, 都築 俊宏, 納富 良文, 篠田 一也, 渡邊 鉄哉, 今田 晋亮, 草野完也, 増 田智, 川手 朋子, 横山 央明, 長谷川 隆祥, 一本 潔, 永田 伸一, 浅井 歩, 渡邉 恭子, 飯田 佑輔, 峯杉 賢治, 後藤 健, 太刀川 純孝, 小川 博之, 松崎恵一, 福田 盛介, 伊藤 琢博, 岡田 則夫, 中坪 俊一, 西野 徹雄, 山崎 敦, 村上 豪, 橋本 樹明, 坂井 真一郎, 小原 新吾, 木本 雄吾, 島﨑 一紀, 山中 理代, 宮崎 英治, 津野 克彦, ほかSolar-C(EUVST)プリプロ準備チーム
    第21回宇宙科学シンポジウム  招待有り

担当経験のある科目(授業)

 1

共同研究・競争的資金等の研究課題

 13

学術貢献活動

 1
  • 企画立案・運営等, パネル司会・セッションチェア等
    Hinode-13/IPELS 2019 LOC 2019年9月2日 - 2019年9月6日

社会貢献活動

 7

メディア報道

 3
  • ニュートンプレス Newton 2024年5月号 https://www.newtonpress.co.jp/dcms_media/image/Newton202405_102-103.jpg 2024年5月 新聞・雑誌
  • 信濃毎日新聞 MGプレス 2023年6月30日 新聞・雑誌
  • 信濃毎日新聞社 MGプレス 2019年12月21日 新聞・雑誌