Updated on 2024/10/22

写真a

 
KITAMURA Naritoshi
 
Organization
Institute for Space-Earth Environmental Research Center for Integrated Data Science Designated assistant professor
Title
Designated assistant professor
External link

Degree 3

  1. 博士(理学) （ 2012.3   東北大学 ） 

  2. 修士(理学) （ 2009.3   東北大学 ） 

  3. 学士(理学) （ 2007.3   東北大学 ） 

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Research Interests 4

  1. 磁気圏

  2. 極域電離圏

  3. 宇宙プラズマ

  4. プラズマ波動

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Research Areas 1

  1. Natural Science / Space and planetary sciences  / 磁気圏物理学

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Research History 9

  1. Institute for Space-Earth Environmental Research (ISEE), Nagoya University   Center for Integrated Data Science (CIDAS)   Designated assistant professor

    2023.11

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    Country：Japan

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  2. Institute for Space-Earth Environmental Research (ISEE), Nagoya University   Division for Ionospheric and Magnetospheric Research   Designated assistant professor

    2022.5 - 2023.10

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  3. 名古屋大学 宇宙地球環境研究所   基盤研究部門 電磁気圏研究部   研究機関研究員

    2022.4

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  4. 東京大学大学院   理学系研究科地球惑星科学専攻   特任研究員

    2018.4 - 2022.3

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  5. Sojo University   Faculty of Engineering, Department of Aerospace Systems Engineering

    2015.4 - 2018.3

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  6. Nagoya University   Solar-Terrestrial Environment Laboratory, Integrated Studies Division

    2012.4 - 2015.3

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  7. 東北大学大学院   理学研究科地球物理学専攻   日本学術振興会 特別研究員(DC2)

    2010.4 - 2012.3

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  8. National Institute of Polar Research

    2010.6 - 2011.3

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  9. 東北大学大学院   理学研究科地球物理学専攻   東北大学グローバルCOEプログラム特待大学院生(SDC)

    2009.6 - 2010.3

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Education 3

  1. 東北大学大学院   理学研究科   地球物理学専攻博士課程後期

    2009.4 - 2012.3

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  2. 東北大学大学院   理学研究科   地球物理学専攻博士課程前期

    2007.4 - 2009.3

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  3. Tohoku University   Faculty of Science   Department of Astronomy and Geophysics

    2003.4 - 2007.3

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Professional Memberships 3

  1. American Geophysical Union

    2007.8

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  2. SOCIETY OF GEOMAGNETISM AND EARTH, PLANETARY AND SPACE SCIENCES

    2006.10

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  3. Japan Geoscience Union

    2006.5

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Awards 3

  1. 大林奨励賞

    2018.11   地球電磁気・地球惑星圏学会   地球極冠域のプラズマ密度構造と低エネルギーイオン流出に関する観測的研究

    北村成寿

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  2. 青葉理学振興会賞

    2012.3   青葉理学振興会  

    北村成寿

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  3. Outstanding Student Paper Award

    2009.11   2009 URSI/COSPAR Workshop on the International Reference Ionosphere  

    北村成寿

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    Award type：Award from international society, conference, symposium, etc. 

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Papers 35

  1. Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth Reviewed International coauthorship

    Naritoshi Kitamura, Takanobu Amano, Yoshiharu Omura, Scott Boardsen, D. J. Gershman, Yoshizumi Miyoshi, M. Kitahara, Yuto Katoh, Hirotsugu Kojima, S. Nakamura, Masafumi Shoji, Y. Saito, shoichiro yokota, B. L. Giles, W. R. Paterson, C. J. Pollock, A. C. Barrie, D. G. Skeberdis, S. Kreisler, Olivier Le Contel, C. T. Russell, Robert J. Strangeway, P.-A. Lindqvist, R. E. Ergun, Roy Torbert, J. L. Burch

    Nature Communications   Vol. 13 ( 1 )   2022.10

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media {LLC}  

    <jats:title>Abstract</jats:title><jats:p>Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA’s Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.</jats:p>

    DOI： 10.1038/s41467-022-33604-2

    DOI： 10.1038/s41467-022-33604-2

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    Other Link： https://www.nature.com/articles/s41467-022-33604-2

  2. On the relationship between energy input to the ionosphere and the ion outflow flux under different solar zenith angles Reviewed International coauthorship International journal

    Naritoshi Kitamura, Kanako Seki, Kunihiro Keika, Yukitoshi Nishimura, Tomoaki Hori, Masafumi Hirahara, Eric J. Lund, Lynn M. Kistler, Robert J. Strangeway

    Earth, Planets and Space   Vol. 73 ( 1 )   2021.11

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media {LLC}  

    <jats:title>Abstract</jats:title><jats:p>The ionosphere is one of the important sources for magnetospheric plasma, particularly for heavy ions with low charge states. We investigate the effect of solar illumination on the number flux of ion outflow using data obtained by the Fast Auroral SnapshoT (FAST) satellite at 3000–4150 km altitude from 7 January 1998 to 5 February 1999. We derive empirical formulas between energy inputs and outflowing ion number fluxes for various solar zenith angle ranges. We found that the outflowing ion number flux under sunlit conditions increases more steeply with increasing electron density in the loss cone or with increasing precipitating electron density (&gt; 50 eV), compared to the ion flux under dark conditions. Under ionospheric dark conditions, weak electron precipitation can drive ion outflow with small averaged fluxes (~ 10<jats:sup>7</jats:sup> cm<jats:sup>−2</jats:sup> s<jats:sup>−1</jats:sup>). The slopes of relations between the Poynting fluxes and outflowing ion number fluxes show no clear dependence on the solar zenith angle. Intense ion outflow events (&gt; 10<jats:sup>8</jats:sup> cm<jats:sup>−2</jats:sup> s<jats:sup>−1</jats:sup>) occur mostly under sunlit conditions (solar zenith angle &lt; 90°). Thus, it is presumably difficult to drive intense ion outflows under dark conditions, because of a lack of the solar illumination (low ionospheric density and/or small scale height owing to low plasma temperature).</jats:p>
    <jats:p><jats:bold>Graphical abstract</jats:bold></jats:p>

    DOI： 10.1186/s40623-021-01532-y

    DOI： 10.1186/s40623-021-01532-y

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    Other Link： https://doi.org/10.1186/s40623-021-01532-y

  3. Energy Transfer Between Hot Protons and Electromagnetic Ion Cyclotron Waves in Compressional Pc5 Ultra‐low Frequency Waves Reviewed International coauthorship International journal

    N. Kitamura, M. Shoji, S. Nakamura, M. Kitahara, T. Amano, Y. Omura, H. Hasegawa, S. A. Boardsen, Y. Miyoshi, Y. Katoh, M. Teramoto, Y. Saito, S. Yokota, M. Hirahara, D. J. Gershman, B. L. Giles, C. T. Russell, R. J. Strangeway, N. Ahmadi, P.‐A. Lindqvist, R. E. Ergun, S. A. Fuselier, J. L. Burch

    Journal of Geophysical Research: Space Physics   Vol. 126 ( 5 )   2021.5

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    The Magnetospheric Multiscale (MMS) spacecraft observed many enhancements of electromagnetic ion cyclotron (EMIC) waves in an event in the late afternoon outer magnetosphere. These enhancements occurred mainly in the troughs of magnetic field intensity associated with a compressional ultralow frequency (ULF) wave. The ULF wave had a period of ∼2–5 min (Pc5 frequency range) and was almost static in the plasma rest frame. The magnetic and ion pressures were in antiphase. They are consistent with mirror-mode type structures. We apply the Wave-Particle Interaction Analyzer method, which can quantitatively investigate the energy transfer between hot anisotropic protons and EMIC waves, to burst-mode data obtained by the four MMS spacecraft. The energy transfer near the cyclotron resonance velocity was identified in the vicinity of the center of troughs of magnetic field intensity, which corresponds to the maxima of ion pressure in the compressional ULF wave. This result is consistent with the idea that the EMIC wave generation is modulated by ULF waves, and preferential locations for the cyclotron resonant energy transfer are the troughs of magnetic field intensity. In these troughs, relatively low resonance velocity due to the lower magnetic field intensity and the enhanced hot proton flux likely contribute to the enhanced energy transfer from hot protons to the EMIC waves by cyclotron resonance. Due to the compressional ULF wave, regions of the cyclotron resonant energy transfer can be narrow (only a few times of the gyroradii of hot resonant protons) in magnetic local time.

    DOI： 10.1029/2020ja028912

    DOI： 10.1029/2020ja028912

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    Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2020JA028912

  4. Observations of the Source Region of Whistler Mode Waves in Magnetosheath Mirror Structures Reviewed International coauthorship International journal

    N. Kitamura, Y. Omura, S. Nakamura, T. Amano, S. A. Boardsen, N. Ahmadi, O. Le Contel, P.‐A. Lindqvist, R. E. Ergun, Y. Saito, S. Yokota, D. J. Gershman, W. R. Paterson, C. J. Pollock, B. L. Giles, C. T. Russell, R. J. Strangeway, J. L. Burch

    Journal of Geophysical Research: Space Physics   Vol. 125 ( 5 )   2020.5

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2019ja027488

    DOI： 10.1029/2019ja027488

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    Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2019JA027488

  5. Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma Reviewed International coauthorship International journal

    N. Kitamura, M. Kitahara, M. Shoji, Y. Miyoshi, H. Hasegawa, S. Nakamura, Y. Katoh, Y. Saito, S. Yokota, D. J. Gershman, A. F. Vinas, B. L. Giles, T. E. Moore, W. R. Paterson, C. J. Pollock, C. T. Russell, R. J. Strangeway, S. A. Fuselier, J. L. Burch

    Science   Vol. 361 ( 6406 ) page： 1000 - 1003   2018.9

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Association for the Advancement of Science (AAAS)  

    Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth’s magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He<sup>+</sup> to energies up to ~2 kilo–electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.

    DOI： 10.1126/science.aap8730

    DOI： 10.1126/science.aap8730

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    Other Link： https://doi.org/10.1126/science.aap8730

  6. Thermal and Low-energy Ion Outflows in and through the Polar Cap Reviewed International coauthorship International journal

    Naritoshi Kitamura, Kanako Seki, Yukitoshi Nishimura, Takumi Abe, Manabu Yamada, Shigeto Watanabe, Atsushi Kumamoto, Atsuki Shinbori, Andrew W. Yau

    Magnetosphere-Ionosphere Coupling in the Solar System     page： 91 - 100   2016.10

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Part of collection (book)   Publisher：John Wiley & Sons, Inc.  

    DOI： 10.1002/9781119066880.ch7

    DOI： 10.1002/9781119066880.ch7

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    Other Link： https://doi.org/10.1002/9781119066880.ch7

  7. Shift of the magnetopause reconnection line to the winter hemisphere under southward IMF conditions: Geotail and MMS observations Reviewed International coauthorship International journal

    N. Kitamura, H. Hasegawa, Y. Saito, I. Shinohara, S. Yokota, T. Nagai, C. J. Pollock, B. L. Giles, T. E. Moore, J. C. Dorelli, D. J. Gershman, L. A. Avanov, W. R. Paterson, V. N. Coffey, M. O. Chandler, J. A. Sauvaud, B. Lavraud, R. B. Torbert, C. T. Russell, R. J. Strangeway, J. L. Burch

    Geophysical Research Letters   Vol. 43 ( 11 ) page： 5581 - 5588   2016.6

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

    At 02:13 UT on 18 November 2015 when the geomagnetic dipole was tilted by −27°, the MMS spacecraft observed southward reconnection jets near the subsolar magnetopause under southward and dawnward interplanetary magnetic field conditions. Based on four-spacecraft estimations of the magnetic field direction near the separatrix and the motion and direction of the current sheet, the location of the reconnection line was estimated to be ~1.8 RE or further northward of MMS. The Geotail spacecraft at GSM Z~1.4 RE also observed southward reconnection jets at the dawnside magnetopause 30–40 min later. The estimated reconnection line location was northward of GSM Z~2 RE. This crossing occurred when MMS observed purely southward magnetic fields in the magnetosheath. The simultaneous observations are thus consistent with the hypothesis that the dayside magnetopause reconnection line shifts from the subsolar point toward the northern (winter) hemisphere due to the effect of geomagnetic dipole tilt.

    DOI： 10.1002/2016GL069095

    DOI： 10.1002/2016GL069095

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    Other Link： https://doi.org/10.1002/2016GL069095

  8. Limited impact of escaping photoelectrons on the terrestrial polar wind flux in the polar cap Reviewed International coauthorship International journal

    N. Kitamura, K. Seki, Y. Nishimura, J. P. McFadden

    Geophysical Research Letters   Vol. 42 ( 9 ) page： 3106 - 3113   2015.5

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

    A statistical analysis using a long-term (over one solar cycle) photoelectron data set obtained by the Fast Auroral SnapshoT satellite demonstrates that photoelectron outflows has little impact on the polar wind ion flux. This result implies that it is the source region of H&lt
    sup&gt
    +&lt
    /sup&gt
    ions in the topside ionosphere and not the photoelectron flux that controls the terrestrial polar wind flux. The polar wind ion flux, estimated from electron outflow does not change with increasing net photoelectron production due to increasing solar activity. The magnitude of a self-created field-aligned potential drop is likely determined so as to equilibrate electron fluxes with ion fluxes regulated by a net production rate of H&lt
    sup&gt
    +&lt
    /sup&gt
    ions. The result suggests that the polar wind H&lt
    sup&gt
    +&lt
    /sup&gt
    ion flux from magnetized terrestrial planets, including Earth-like exoplanets, can be estimated once the composition and temperature of its atmosphere, which determine the net ion production rate, are known. Key Points The polar wind ion flux does not change with increasing solar activity The magnitude of the field-aligned potential drop is larger at solar maximum The polar wind ion flux is likely regulated by a net production rate of H&lt
    sup&gt
    +&lt
    /sup&gt
    ions

    DOI： 10.1002/2015GL063452

    DOI： 10.1002/2015GL063452

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    Other Link： https://doi.org/10.1002/2015GL063452

  9. Reduction of the field-aligned potential drop in the polar cap during large geomagnetic storms Reviewed International coauthorship International journal

    N. Kitamura, K. Seki, Y. Nishimura, T. Hori, N. Terada, T. Ono, R. J. Strangeway

    Journal of Geophysical Research: Space Physics   Vol. 118 ( 8 ) page： 4864 - 4874   2013.8

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1002/jgra.50450

    DOI： 10.1002/jgra.50450

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    Other Link： https://doi.org/10.1002/jgra.50450

  10. Storm-time electron density enhancement in the cleft ion fountain Reviewed International coauthorship International journal

    N. Kitamura, Y. Nishimura, M. O. Chandler, T. E. Moore, N. Terada, T. Ono, A. Shinbori, A. Kumamoto

    Journal of Geophysical Research: Space Physics   Vol. 117 ( A11 ) page： n/a - n/a   2012.11

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2012ja017900

    DOI： 10.1029/2012ja017900

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    Other Link： https://doi.org/10.1029/2012ja017900

  11. Photoelectron flows in the polar wind during geomagnetically quiet periods Reviewed International coauthorship International journal

    N. Kitamura, K. Seki, Y. Nishimura, N. Terada, T. Ono, T. Hori, R. J. Strangeway

    Journal of Geophysical Research: Space Physics   Vol. 117 ( A7 ) page： n/a - n/a   2012.7

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2011ja017459

    DOI： 10.1029/2011ja017459

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    Other Link： https://doi.org/10.1029/2011ja017459

  12. Solar zenith angle dependence of plasma density and temperature in the polar cap ionosphere and low-altitude magnetosphere during geomagnetically quiet periods at solar maximum Reviewed International coauthorship International journal

    N. Kitamura, Y. Ogawa, Y. Nishimura, N. Terada, T. Ono, A. Shinbori, A. Kumamoto, V. Truhlik, J. Smilauer

    Journal of Geophysical Research: Space Physics   Vol. 116 ( A8 ) page： n/a - n/a   2011.8

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2011ja016631

    DOI： 10.1029/2011ja016631

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    Other Link： https://doi.org/10.1029/2011ja016631

  13. Observations of very-low-energy (<10 eV) ion outflows dominated by O+ ions in the region of enhanced electron density in the polar cap magnetosphere during geomagnetic storms Reviewed International coauthorship International journal

    N. Kitamura, Y. Nishimura, T. Ono, Y. Ebihara, N. Terada, A. Shinbori, A. Kumamoto, T. Abe, M. Yamada, S. Watanabe, A. Matsuoka, A. W. Yau

    Journal of Geophysical Research: Space Physics   Vol. 115 ( A11 ) page： n/a - n/a   2010.11

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2010ja015601

    DOI： 10.1029/2010ja015601

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    Other Link： https://doi.org/10.1029/2010ja015601

  14. Temporal variations and spatial extent of the electron density enhancements in the polar magnetosphere during geomagnetic storms Reviewed International coauthorship International journal

    N. Kitamura, Y. Nishimura, T. Ono, A. Kumamoto, A. Shinbori, M. Iizima, A. Matsuoka, M. R. Hairston

    Journal of Geophysical Research: Space Physics   Vol. 115 ( A7 )   2010.7

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2009ja014499

    DOI： 10.1029/2009ja014499

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    Other Link： https://doi.org/10.1029/2009ja014499

  15. Seasonal variations of the electron density distribution in the polar region during geomagnetically quiet periods near solar maximum Reviewed International journal

    N. Kitamura, A. Shinbori, Y. Nishimura, T. Ono, M. Iizima, A. Kumamoto

    Journal of Geophysical Research: Space Physics   Vol. 114 ( A1 ) page： n/a - n/a   2009.1

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

    DOI： 10.1029/2008ja013288

    DOI： 10.1029/2008ja013288

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    Other Link： https://doi.org/10.1029/2008ja013288

  16. Reimei Satellite Observations of Alfvénic Interaction Modulating Inverted‐V Electrons and Filamentary Auroral Forms at the Poleward Edge of a Discrete Arc Reviewed International journal

    Masafumi Hirahara, Yusuke Ebihara, Naritoshi Kitamura, Takeshi Sakanoi, Kazushi Asamura, Taku Takada, Hirobumi Saito

    Journal of Geophysical Research: Space Physics   Vol. 129 ( 10 )   2024.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2024JA032650

  17. Statistical Observations of Proton‐Band Electromagnetic Ion Cyclotron Waves in the Outer Magnetosphere: Full Wavevector Determination Reviewed International coauthorship International journal

    S. Toledo‐Redondo, J. H. Lee, S. K. Vines, I. F. Albert, M. André, A. Castilla, J. P. Dargent, H. S. Fu, S. A. Fuselier, V. Genot, D. B. Graham, N. Kitamura, Yu. V. Khotyaintsev, B. Lavraud, V. Montagud‐Camps, E. A. Navarro, C. Norgren, D. Perrone, T. D. Phan, J. Portí, A. Salinas, J. E. Stawarz, A. Vaivads

    Journal of Geophysical Research: Space Physics   Vol. 129 ( 5 )   2024.5

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

    Abstract

    Electromagnetic Ion Cyclotron (EMIC) waves mediate energy transfer from the solar wind to the magnetosphere, relativistic electron precipitation, or thermalization of the ring current population, to name a few. How these processes take place depends on the wave properties, such as the wavevector and polarization. However, inferring the wavevector from in‐situ measurements is problematic since one needs to disentangle spatial and time variations. Using 8 years of Magnetospheric Multiscale (MMS) mission observations in the dayside magnetosphere, we present an algorithm to detect proton‐band EMIC waves in the Earth's dayside magnetosphere, and find that they are present roughly 15% of the time. Their normalized frequency presents a dawn‐dusk asymmetry, with waves in the dawn flank magnetosphere having larger frequency than in the dusk, subsolar, and dawn near subsolar region. It is shown that the observations are unstable to the ion cyclotron instability. We obtain the wave polarization and wavevector by comparing Single Value Decomposition and Ampere methods. We observe that for most waves the perpendicular wavenumber (k<sub>⊥</sub>) is larger than the inverse of the proton gyroradius (ρ<sub>i</sub>), that is, k<sub>⊥</sub>ρ<sub>i</sub> &gt; 1, while the parallel wavenumber is smaller than the inverse of the ion gyroradius, that is, k<sub>‖</sub>ρ<sub>i</sub> &lt; 1. Left‐hand polarized waves are associated with small wave normal angles (θ<sub>Bk</sub> &lt; 30°), while linearly polarized waves are associated with large wave normal angles (θ<sub>Bk</sub> &gt; 30°). This work constitutes, to our knowledge, the first attempt to statistically infer the full wavevector of proton‐band EMIC waves observed in the outer magnetosphere.

    DOI： 10.1029/2024ja032516

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  18. Statistical analysis of high-frequency whistler waves at Earth's bow shock: Further support for stochastic shock drift acceleration Reviewed International coauthorship International journal

    Takanobu Amano, Miki Masuda, Mitsuo Oka, Naritoshi Kitamura, Olivier Le Contel, Daniel J. Gershman

    Physics of Plasmas   Vol. 31 ( 4 )   2024.4

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：AIP Publishing  

    We statistically investigate high-frequency whistler waves (with frequencies higher than ∼10% of the local electron cyclotron frequency) at Earth's bow shock using magnetospheric multi-scale (MMS) spacecraft observations. We focus specifically on the wave power within the shock transition layer, where we expect electron acceleration via stochastic shock drift acceleration (SSDA) to occur associated with efficient pitch-angle scattering by whistler waves. We find that the wave power is positively correlated with both the Alfvén Mach number in the normal incidence frame MA and in the de Hoffmann–Teller frame MA/cos θBn. The empirical relation with MA/cos θBn is compared with the theory of SSDA that predicts a threshold wave power proportional to (MA/cos θBn)−2. The result suggests that the wave power exceeds the theoretical threshold for MA/cos θBn≳30–60, beyond which efficient electron acceleration is expected. This aligns very well with previous statistical analysis of electron acceleration at Earth's bow shock [Oka et al., Geophys. Res. Lett. 33, 5–6 (2006)]. Therefore, we consider that this study provides further support for SSDA as the mechanism of electron acceleration at Earth's bow shock. At higher-Mach-number astrophysical shocks, SSDA will be able to inject electrons into the diffusive shock acceleration process for subsequent acceleration to cosmic-ray energies.

    DOI： 10.1063/5.0196502

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  19. Transport Path of Cold‐Dense Plasmas in the Dusk Magnetotail Plasma Sheet: MMS Observations Reviewed International coauthorship

    M. N. Nishino, H. Hasegawa, Y. Saito, N. Kitamura, Y. Miyashita, T. Nagai, S. Yokota, C. T. Russell, D. J. Gershman, B. L. Giles

    Journal of Geophysical Research: Space Physics   Vol. 127 ( 1 )   2022.1

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    DOI： 10.1029/2021ja029747

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  20. Kinetic Interaction of Cold and Hot Protons With an Oblique EMIC Wave Near the Dayside Reconnecting Magnetopause Reviewed International coauthorship International journal

    S. Toledo-Redondo, J. H. Lee, S. K. Vines, D. L. Turner, R. C. Allen, M. Andr{\'{e } }, S. A. Boardsen, J. L. Burch, R. E. Denton, H. S. Fu, S. A. Fuselier, D. J. Gershman, B. Giles, D. B. Graham, N. Kitamura, Yu. V. Khotyaintsev, B. Lavraud, O. Le Contel, W. Y. Li, T. E. Moore, E. A. Navarro, J. Port{\'{\i } }, A. Salinas, A. Vinas

    Geophysical Research Letters   Vol. 48 ( 8 )   2021.4

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    DOI： 10.1029/2021gl092376

    DOI： 10.1029/2021gl092376

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  21. Factors Controlling O+ and H+ Outflow in the Cusp During a Geomagnetic Storm: FAST/TEAMS Observations Reviewed International coauthorship International journal

    K. Zhao, L .M. Kistler, E. J. Lund, N. Nowrouzi, N. Kitamura, R. J. Strangeway

    Geophysical Research Letters   Vol. 47 ( 11 )   2020.6

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    DOI： 10.1029/2020gl086975

    DOI： 10.1029/2020gl086975

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  22. Observational Evidence for Stochastic Shock Drift Acceleration of Electrons at the Earth's Bow Shock Reviewed International coauthorship

    T. Amano, T. Katou, N. Kitamura, M. Oka, Y. Matsumoto, M. Hoshino, Y. Saito, S. Yokota, B. L. Giles, W. R. Paterson, C. T. Russell, O. Le Contel, R. E. Ergun, P. A. Lindqvist, D. L. Turner, J. F. Fennell, J. B. Blake

    Physical Review Letters   Vol. 124 ( 6 )   2020.2

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    © 2020 us. © 2020 American Physical Society. American Physical Society. The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.

    DOI： 10.1103/PhysRevLett.124.065101

    DOI： 10.1103/PhysRevLett.124.065101

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  23. Statistical Study on Electron and Ion Temperatures in the Near-Earth Reconnection and Magnetic Pileup Regions Reviewed International coauthorship

    K. Watanabe, K. Keika, M. Hoshino, N. Kitamura, Y. Saito, B. L. Giles, W. R. Paterson

    Geophysical Research Letters   Vol. 46 ( 24 ) page： 14223 - 14229   2019.12

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    © 2019. American Geophysical Union. All Rights Reserved. Plasma heating during the magnetic reconnection is not well understood, particularly in terms of adiabaticity, heating rate, and electron-ion temperature ratio. This study focuses on macroscopic profiles of Ti, Te, and Ti/Te in the near-Earth magnetotail, using data obtained from Magnetospheric Multiscale. Observation points are categorized into three different regions: low-beta/high-beta inflow region, the reconnection sites, and magnetic pileup regions. From low-beta inflow region to high-beta inflow region, both Ti and Te increase and electron entropy is constant. Ion entropy, on the other hand, increases across the transition. Inside the reconnection site, Ti and Te increase, and entropies remain constant. From the outflow region to the pileup region, electrons are selectively heated. Electron entropy increases in the transition. This statistical study suggests that nonadiabatic heating occurs around the plasma sheet boundary layer for ions and at the early stage of magnetic field pileup for electrons.

    DOI： 10.1029/2019GL084837

    DOI： 10.1029/2019GL084837

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  24. Cusp and Nightside Auroral Sources of O+ in the Plasma Sheet Reviewed International coauthorship International journal

    L. M. Kistler, C. G. Mouikis, K. Asamura, S. Yokota, S. Kasahara, Y. Miyoshi, K. Keika, A. Matsuoka, I. Shinohara, T. Hori, N. Kitamura, S. M. Petrinec, I. J. Cohen, D. C. Delcourt

    Journal of Geophysical Research: Space Physics   Vol. 124 ( 12 ) page： 10036 - 10047   2019.12

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    DOI： 10.1029/2019ja027061

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  25. EMIC Waves Converted From Equatorial Noise Due to M/Q = 2 Ions in the Plasmasphere: Observations From Van Allen Probes and Arase Reviewed International coauthorship International journal

    Y. Miyoshi, S. Matsuda, S. Kurita, K. Nomura, K. Keika, M. Shoji, N. Kitamura, Y. Kasahara, A. Matsuoka, I. Shinohara, K. Shiokawa, S. Machida, O. Santolik, S. A. Boardsen, R. B. Horne, J. F. Wygant

    Geophysical Research Letters   Vol. 46 ( 11 ) page： 5662 - 5669   2019.6

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    DOI： 10.1029/2019gl083024

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  26. Reconstruction of the Electron Diffusion Region of Magnetotail Reconnection Seen by the MMS Spacecraft on 11 July 2017 Reviewed International coauthorship International journal

    H. Hasegawa, R. E. Denton, R. Nakamura, K. J. Genestreti, T. K. M. Nakamura, K.-J. Hwang, T. D. Phan, R. B. Torbert, J. L. Burch, B. L. Giles, D. J. Gershman, C. T. Russell, R. J. Strangeway, P.-A. Lindqvist, Y. V. Khotyaintsev, R. E. Ergun, N. Kitamura, Y. Saito

    Journal of Geophysical Research: Space Physics   Vol. 124 ( 1 ) page： 122 - 138   2018.11

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    ©2018. American Geophysical Union. All Rights Reserved. We present results from the reconstruction of the electron diffusion region of magnetotail reconnection observed by the Magnetospheric Multiscale (MMS) spacecraft on 11 July 2017. In the event, the conditions were suited for the reconstruction technique, developed by Sonnerup et al. (2016, https://doi.org/10.1002/2016JA022430), that produces magnetic field and electron streamline maps based on a two-dimensional, time-independent, inertialess form of electron magnetohydrodynamic equation, assuming an approximately symmetric current sheet and negligible guide magnetic field. For such a two-dimensional and steady structure, the X line orientation can be estimated from a method based on Ampère's law using single-spacecraft measurements of the magnetic field and electric current density. Our reconstruction results indicate that although the X point was not captured inside its tetrahedron, MMS approached the X point as close as one electron inertial length ~27 km. The opening angle of the recovered separatrix field line, combined with theory, suggests that the dimensionless reconnection rate was 0.17, which is consistent with the measured reconnection electric field 2–4 mV/m. The stagnation point of the reconstructed electron flow is shifted earthward of the X point by ~90 km, one possible interpretation of which is discussed. The energy conversion rate j · E′ in the electron frame tends to be higher near the stagnation point, consistent with earlier observations and simulations, and is not correlated with the amplitude of broadband electrostatic waves observed in the upper-hybrid frequency range. The latter suggests that the waves did not contribute to energy dissipation in this particular electron diffusion region.

    DOI： 10.1029/2018ja026051

    DOI： 10.1029/2018ja026051

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  27. Seasonal and Solar Wind Control of the Reconnection Line Location on the Earth's Dayside Magnetopause Reviewed International coauthorship International journal

    Y. Hoshi, H. Hasegawa, N. Kitamura, Y. Saito, V. Angelopoulos

    Journal of Geophysical Research: Space Physics   Vol. 123 ( 9 ) page： 7498 - 7512   2018.9

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    DOI： 10.1029/2018ja025305

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  28. A Statistical Study of Slow-Mode Shocks Observed by MMS in the Dayside Magnetopause Reviewed International coauthorship International journal

    N. K. Walia, K. Seki, M. Hoshino, T. Amano, N. Kitamura, Y. Saito, S. Yokota, C. J. Pollock, B. L. Giles, T. E. Moore, R. B. Torbert, C. T. Russell, J. L. Burch

    Geophysical Research Letters   Vol. 45 ( 10 ) page： 4675 - 4684   2018.5

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    DOI： 10.1029/2018gl077580

    DOI： 10.1029/2018gl077580

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  29. Reconstruction of the electron diffusion region observed by the Magnetospheric Multiscale spacecraft: First results Reviewed International coauthorship International journal

    H. Hasegawa, B. U.Ö. Sonnerup, R. E. Denton, T. D. Phan, T. K.M. Nakamura, B. L. Giles, D. J. Gershman, J. C. Dorelli, J. L. Burch, R. B. Torbert, C. T. Russell, R. J. Strangeway, P. A. Lindqvist, Y. V. Khotyaintsev, R. E. Ergun, P. A. Cassak, N. Kitamura, Y. Saito

    Geophysical Research Letters   Vol. 44 ( 10 ) page： 4566 - 4574   2017.5

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    We present first results of the reconstruction of the electron diffusion region (EDR) based on a two-dimensional, incompressible, and inertialess version of the electron magnetohydrodynamics equations. The method is applied to 30 ms resolution magnetic field, and electron moments data taken when the Magnetospheric Multiscale (MMS) spacecraft observed an EDR of near-antiparallel magnetopause reconnection on 16 October 2015. An X-type magnetic field configuration and quadrupolar Hall fields, consistent with the electron inflow and outflow, are successfully recovered. While MMS encountered a region of significant energy dissipation on the magnetospheric side of the sub-ion-scale current sheet, the reconstructions show that the MMS tetrahedron missed the X line by a distance of a few kilometers (~2 electron inertial lengths). The estimated reconnection electric field is 0.42–0.98 mV/m, equivalent to the dimensionless reconnection rate of 0.11–0.25. Signatures of three-dimensional structures and/or time-dependent processes are also identified.

    DOI： 10.1002/2017GL073163

    DOI： 10.1002/2017GL073163

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  30. Biogenic oxygen from Earth transported to the Moon by a wind of magnetospheric ions Reviewed International journal

    Kentaro Terada, Shoichiro Yokota, Yoshifumi Saito, Naritoshi Kitamura, Kazushi Asamura, Masaki N. Nishino

    Nature Astronomy   Vol. 1 ( 2 )   2017.2

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

    DOI： 10.1038/s41550-016-0026

    DOI： 10.1038/s41550-016-0026

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  31. Inverse energy dispersion of energetic ions observed in the magnetosheath Reviewed International coauthorship International journal

    S. H. Lee, D. G. Sibeck, K. J. Hwang, Y. Wang, M. V. D. Silveira, M. C. Fok, B. H. Mauk, I. J. Cohen, J. M. Ruohoniemi, N. Kitamura, J. L. Burch, B. L. Giles, R. B. Torbert, C. T. Russell, M. Lester

    Geophysical Research Letters   Vol. 43 ( 14 ) page： 7338 - 7347   2016.7

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    We present a case study of energetic ions observed by the Energetic Particle Detector (EPD) on the Magnetospheric Multiscale spacecraft in the magnetosheath just outside the subsolar magnetopause that occurred at 1000Â UT on 8 December 2015. As the magnetopause receded inward, the EPD observed a burst of energetic (∼50–1000Â keV) proton, helium, and oxygen ions that exhibited an inverse dispersion, with the lowest energy ions appearing first. The prolonged interval of fast antisunward flow observed in the magnetosheath and transient increases in the H components of global ground magnetograms demonstrate that the burst appeared at a time when the magnetosphere was rapidly compressed. We attribute the inverse energy dispersion to the leakage along reconnected magnetic field lines of betatron-accelerated energetic ions in the magnetosheath, and a burst of reconnection has an extent of about 1.5Â RE using combined Super Dual Auroral Radar Network radar and EPD observations.

    DOI： 10.1002/2016GL069840

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  32. Decay of mesoscale flux transfer events during quasi-continuous spatially extended reconnection at the magnetopause Reviewed International coauthorship International journal

    H. Hasegawa, N. Kitamura, Y. Saito, T. Nagai, I. Shinohara, S. Yokota, C. J. Pollock, B. L. Giles, J. C. Dorelli, D. J. Gershman, L. A. Avanov, S. Kreisler, W. R. Paterson, M. O. Chandler, V. Coffey, J. L. Burch, R. B. Torbert, T. E. Moore, C. T. Russell, R. J. Strangeway, G. Le, M. Oka, T. D. Phan, B. Lavraud, S. Zenitani, M. Hesse

    Geophysical Research Letters   Vol. 43 ( 10 ) page： 4755 - 4762   2016.5

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    We present observations on 2 October 2015 when the Geotail spacecraft, near the Earth's equatorial plane, and the Magnetospheric Multiscale (MMS) spacecraft, at midsouthern latitudes, simultaneously encountered southward jets from dayside magnetopause reconnection under southward interplanetary magnetic field conditions. The observations show that the equatorial reconnection site under modest solar wind Alfvén Mach number conditions remained active almost continuously for hours and, at the same time, extended over a wide range of local times (≥4 h). The reconnection jets expanded toward the magnetosphere with distance from the reconnection site. Geotail, closer to the reconnection site, occasionally encountered large-amplitude mesoscale flux transfer events (FTEs) with durations about or less than 1 min. However, MMS subsequently detected no or only smaller-amplitude corresponding FTE signatures. It is suggested that during quasi-continuous spatially extended reconnection, mesoscale FTEs decay as the jet spatially evolves over distances between the two spacecraft of ≥350 ion inertial lengths.

    DOI： 10.1002/2016GL069225

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  33. Thick escaping magnetospheric ion layer in magnetopause reconnection with MMS observations Reviewed International coauthorship International journal

    T. Nagai, N. Kitamura, H. Hasegawa, I. Shinohara, S. Yokota, Y. Saito, R. Nakamura, B. L. Giles, C. Pollock, T. E. Moore, J. C. Dorelli, D. J. Gershman, W. R. Paterson, L. A. Avanov, M. O. Chandler, V. Coffey, J. A. Sauvaud, B. Lavraud, C. T. Russell, R. J. Strangeway, M. Oka, K. J. Genestreti, J. L. Burch

    Geophysical Research Letters   Vol. 43 ( 12 ) page： 6028 - 6035   2016

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    The structure of asymmetric magnetopause reconnection is explored with multiple point and high-time-resolution ion velocity distribution observations from the Magnetospheric Multiscale mission. On 9 September 2015, reconnection took place at the magnetopause, which separated the magnetosheath and the magnetosphere with a density ratio of 25:2. The magnetic field intensity was rather constant, even higher in the asymptotic magnetosheath. The reconnected field line region had a width of approximately 540 km. In this region, streaming and gyrating ions are discriminated. The large extension of the reconnected field line region toward the magnetosheath can be identified where a thick layer of escaping magnetospheric ions was formed. The scale of the magnetosheath side of the reconnected field line region relative to the scale of its magnetospheric side was 4.5:1.

    DOI： 10.1002/2016GL069085

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  34. Modeling solar zenith angle effects on the polar wind Reviewed International coauthorship International journal

    A. Glocer, N. Kitamura, G. Toth, T. Gombosi

    Journal of Geophysical Research: Space Physics   Vol. 117 ( A4 ) page： n/a - n/a   2012.4

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    DOI： 10.1029/2011ja017136

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  35. Fundamental characteristics of field-aligned auroral acceleration derived from AKR spectra Reviewed International coauthorship International journal

    A. Morioka, Y. Miyoshi, N. Kitamura, H. Misawa, F. Tsuchiya, J. D. Menietti, F. Honary

    Journal of Geophysical Research: Space Physics   Vol. 117 ( A2 ) page： n/a - n/a   2012.2

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    DOI： 10.1029/2011ja017137

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▼display all

To the head of Papers.▲

MISC 1

  1. Picture of Geospace Revealed by a Quarter of a Century of Observation of the Akebono (EXOS-D) Satellite and Future Perspective: 4. Ion Outflow from the Polar Ionosphere Reviewed International coauthorship

    阿部琢美, 渡部重十, YAU Andrew, 北村成寿

    プラズマ・核融合学会誌   Vol. 98 ( 11 )   2022

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To the head of MISC.▲

Presentations 78

  1. Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth Invited International coauthorship International conference

    Naritoshi Kitamura

    The 7th Asia-Pacific Conference on Plasma Physics (AAPPS-DPP2023)  2023.11.14 

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    Event date： 2023.11

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

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  2. Direct Measurements of Two-Way Wave-Particle Energy Transfer in a Collisionless Space Plasma Invited International coauthorship International conference

    Naritoshi Kitamura

    AAPPS-DPP 2019  2019.11.4 

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    Event date： 2019.11

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

    Venue：Hefei   Country：China  

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  3. Direct Measurements of Two-Way Wave-Particle Energy Transfer in a Collisionless Space Plasma Invited

    北村成寿

    実験室・宇宙プラズマ研究会「乱流・輸送・粒子加速」  2019.3.11 

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    Event date： 2019.3

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

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  4. Direct Measurements of Two-Way Wave-Particle Energy Transfer in a Collisionless Space Plasma Invited International coauthorship International conference

    Naritoshi Kitamura

    Kyoto Workshop on Nonlinear Wave-Particle Interactions in Plasmas  2018.11.19 

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    Event date： 2018.11

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

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  5. 2024年5月の巨大磁気嵐時のリングカレントの特性 International coauthorship

    北村成寿

    第21回 ERGサイエンス会議  2024.9.10 

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    Event date： 2024.9

    Language：Japanese   Presentation type：Oral presentation (general)  

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  6. Modeling of seasonal and solar activity dependence of the storm-time cusp ion outflows International coauthorship International conference

    Naritoshi Kitamura

    JpGU meeting 2024  2024.5.27 

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    Event date： 2024.5

    Language：English   Presentation type：Oral presentation (general)  

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  7. Limited impact of escaping photoelectrons on the terrestrial polar wind flux in the polar cap、磁気嵐時のカスプにおけるイオン流出のモデリング International coauthorship

    北村 成寿

    ISEE研究集会 宇宙プラズマ・恒星放射が惑星超高層大気・衛星表層環境に及ぼす影響  2024.3.27 

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    Event date： 2024.3

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  8. カスプ周辺の広帯域(BBELF)波動の統計解析、磁気嵐時のカスプにおけるイオン流出のモデリング International coauthorship

    北村 成寿

    ISEE研究集会 太陽地球惑星圏の研究領域における将来衛星計画検討会 FACTORS研究集会  2024.3.22 

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    Event date： 2024.3

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  9. 大磁気嵐時のO+が支配的な地球近傍朝側リングカレントイオンの観測 International coauthorship

    北村 成寿

    第20回 ERGサイエンス会議  2024.3.14 

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    Event date： 2024.3

    Language：Japanese   Presentation type：Oral presentation (general)  

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  10. Modeling of acceleration of outflowing ions in the storm-time cusp International coauthorship

    Naritoshi Kitamura

    Workshop on Low Energy Plasma in the goespace  2024.2.5 

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    Event date： 2024.2

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  11. Observation and modeling of storm-time cusp ion outflows International coauthorship International conference

    Naritoshi Kitamura

    AGU fall meeting 2023  2023.12.15 

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    Event date： 2023.12

    Language：English   Presentation type：Poster presentation  

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  12. Observational evidence of nonlinear growth of whistler-mode waves around quasi-perpendicular bow shocks International coauthorship International conference

    Naritoshi Kitamura

    AGU fall meeting 2023  2023.12.12 

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    Event date： 2023.12

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  13. Wave-particle interactions observed by MMS

    Naritoshi Kitamura

    Contribution of BepiColombo to heliosphere system science: heliosphere/planetary magnetosphere  2023.11.8 

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    Event date： 2023.11

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  14. Statistical study on broad band ELF waves in and near the cusp International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting  2023.9.24 

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    Event date： 2023.9

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  15. Modeling of acceleration of outflowing ions in the storm-time cusp International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting  2023.9.26 

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    Event date： 2023.9

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  16. Energy input to the ionosphere and ELF waves during geomagnetic storm events in the cusp International coauthorship International conference

    Naritoshi Kitamura

    GEM workshop 2023  2023.6.13 

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    Event date： 2023.6

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  17. Energy input to the ionosphere and ELF waves during geomagnetic storm events in the cusp International coauthorship International conference

    Naritoshi Kitamura

    JpGU meeting 2023  2023.5.24 

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    Event date： 2023.5

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  18. Observational evidence of nonlinear growth of whistler-mode waves in an outflow of magnetopause reconnection International coauthorship International conference

    Naritoshi Kitamura

    JpGU meeting 2023  2023.5.22 

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  19. Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth International coauthorship International conference

    Naritoshi Kitamura

    Symposium on the Future of Heliospheric Science: From Geotailand Beyond  2023.3.28 

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    Event date： 2023.3

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  20. Direct observations of energy transfer from resonant electrons to whistler-mode waves (dayside reconnection, magnetosheath, and bow shock) International coauthorship

    Naritoshi Kitamura

    “Physics and application of whistler waves” and “Future perspective of study on nonlinear wave-particle interaction”  2023.3.16 

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    Event date： 2023.3

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  21. Direct observations of energy transfer from resonant electrons to whistler-mode waves near the dayside magnetopause reconnection International coauthorship International conference

    Naritoshi Kitamura

    AGU Fall Meeting 2022  2022.12.15 

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    Event date： 2022.12

    Language：English   Presentation type：Oral presentation (general)  

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  22. On the Relationship between Energy Input to the Earth’s Polar Ionosphere and the Ion Outflow Flux under Different Solar Zenith Angles International coauthorship International conference

    Naritoshi Kitamura

    AGU Fall Meeting 2022  2022.12.15 

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    Event date： 2022.12

    Language：English   Presentation type：Poster presentation  

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  23. Observational evidence of nonlinear growth of whistler-mode waves around quasi-perpendicular bow shocks International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting  2022.11.5 

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    Event date： 2022.11

    Language：Japanese   Presentation type：Oral presentation (general)  

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  24. On the relationship between energy input to the ionosphere and the ion outflow flux under different solar zenith angles Invited

    Naritoshi Kitamura

    Workshop on Low Energy Plasma in the Geospace  2022.9.22 

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    Event date： 2022.9

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

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  25. Measurements of nongyrotropic electrons around the cyclotron resonance velocity in whistler-mode waves

    Naritoshi Kitamura

    JpGU meeting 2022  2022.5.22 

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    Event date： 2022.5 - 2022.6

    Language：Japanese   Presentation type：Oral presentation (general)  

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  26. On the relationship between energy input to the ionosphere and the ion outflow flux under different solar zenith angles

    Naritoshi Kitamura

    JpGU meeting 2022  2022.5.26 

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    Event date： 2022.5 - 2022.6

    Language：English   Presentation type：Oral presentation (general)  

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  27. Measurements of nongyrotropic electrons around the cyclotron resonance velocity in whistler-mode waves

    Naritoshi Kitamura

    8th MMS Community workshop  2022.5.13 

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    Event date： 2022.5

    Language：English   Presentation type：Oral presentation (general)  

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  28. Direct observations of electron current in whistler-mode waves

    Naritoshi Kitamura

    AGU Fall Meeting 2021  2021.12.15 

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    Event date： 2021.12

    Language：English   Presentation type：Poster presentation  

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  29. Measurements of nongyrotropic electrons around the cyclotron resonance velocity in whistler-mode waves

    Naritoshi Kitamura

    SGEPSS fall meeting  2021.11.2 

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    Event date： 2021.10 - 2021.11

    Language：Japanese   Presentation type：Oral presentation (general)  

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  30. Energy Transfer Between Hot Protons and Electromagnetic Ion Cyclotron Waves in Compressional Pc5 Ultra-low Frequency Waves

    Naritoshi Kitamura

    7th MMS Community Workshop  2021.10.21 

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    Event date： 2021.10

    Language：English   Presentation type：Oral presentation (general)  

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  31. Energy Transfer Between Hot Protons and Electromagnetic Ion Cyclotron Waves in Compressional Pc5 Ultra-low Frequency Waves

    Naritoshi Kitamura

    VGEM workshop 2021  2021.7.26 

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    Event date： 2021.7

    Language：English   Presentation type：Poster presentation  

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  32. On the relationship between energy input to the ionosphere and the ion outflow flux under different solar zenith angles

    Naritoshi Kitamura

    VGEM Workshop 2021  2021.7.27 

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    Event date： 2021.7

    Language：English   Presentation type：Oral presentation (general)  

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  33. Limited impact of escaping photoelectrons on the terrestrial polar wind flux in the polar cap

    Naritoshi Kitamura

    MACH workshop  2021.6.16 

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    Event date： 2021.6

    Language：English   Presentation type：Oral presentation (general)  

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  34. Solar zenith angle dependence of relationships between energy inputs to the ionosphere and ion outflow fluxes

    Naritoshi Kitamura

    MACH workshop  2021.6.16 

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    Event date： 2021.6

    Language：English   Presentation type：Poster presentation  

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  35. Observation of non-gyrotropy of electrons caused by wave-particle interaction with intense whistler mode waves in mirror mode structures in the magnetosheath

    Naritoshi Kitamura

    JpGU meeting 2021  2021.6.4 

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    Event date： 2021.5 - 2021.6

    Language：Japanese   Presentation type：Oral presentation (general)  

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  36. FAST衛星とあけぼの衛星による大気流出の観測

    北村 成寿

    研究集会 「宇宙地球結合系における物理機構・素過程に関する統合的研究形態・体系の構築・推進」  2021.3.16 

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    Event date： 2021.3

    Language：Japanese   Presentation type：Oral presentation (general)  

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  37. Modulation of energy transfer between hot protons and electromagnetic ion cyclotron waves by compressional Pc5 ULF waves

    Naritoshi Kitamura

    AGU Fall Meeting 2020  2020.12.14 

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    Event date： 2020.12

    Language：English   Presentation type：Poster presentation  

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  38. Direct Measurements of Two-Way Wave-Particle Energy Transfer in a Collisionless Space Plasma

    Naritoshi Kitamura

    VERSIM 2020  2020.11.19 

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    Event date： 2020.11

    Language：English   Presentation type：Oral presentation (general)  

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  39. Observations of the Source Region of Whistler Mode Waves in Magnetosheath Mirror Structures

    Naritoshi Kitamura

    VERSIM 2020  2020.11.17 

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    Event date： 2020.11

    Language：English   Presentation type：Poster presentation  

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  40. Estimation of inhomogeneity factor for the interaction between protons and EMIC wave

    Naritoshi Kitamura

    SGEPSS fall meeting  2020.11.2 

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    Event date： 2020.11

    Language：Japanese   Presentation type：Oral presentation (general)  

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  41. Cold ion outflow and the transport to the inner magnetosphere

    Naritoshi Kitamura

    VGEM Summer Workshop 2020  2020.7.22 

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    Event date： 2020.7

    Language：English   Presentation type：Oral presentation (general)  

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  42. Modulation of energy transfer between hot protons and electromagnetic ion cyclotron waves by compressional Pc5 ULF waves

    Naritoshi Kitamura

    VGEM Summer Workshop 2020  2020.7.21 

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    Event date： 2020.7

    Language：English   Presentation type：Poster presentation  

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  43. Direct measurements of energy transfer from hot protons to EMIC waves in ULF waves at the outer magnetosphere

    Naritoshi Kitamura

    JpGU meeting 2020  2020.7.12 

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    Event date： 2020.7

    Language：English   Presentation type：Poster presentation  

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  44. FACTORS 計画におけるイオン流出の観測、関連計測機器の検討状況

    北村成寿

    第20回宇宙科学シンポジウム  2020.1.8 

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    Event date： 2020.1

    Language：Japanese   Presentation type：Poster presentation  

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  45. Whistler mode waves near the magnetic field intensity minimum of mirror structures in magnetosheath

    Naritoshi Kitamura

    2019.12.10 

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    Event date： 2019.12

    Language：English   Presentation type：Poster presentation  

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  46. Spatial scale of whistler mode waves in magnetic dips in the magnetosheath

    2019.10.23 

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    Event date： 2019.10

    Language：Japanese   Presentation type：Poster presentation  

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  47. 磁気圏シース領域のミラー構造内の磁場極小付近での小スケールのホイッスラーモード波動

    北村成寿

    実験室・宇宙プラズマ研究集会  2019.9.17 

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    Event date： 2019.9

    Language：Japanese   Presentation type：Oral presentation (general)  

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  48. FACTORS衛星計画におけるイオン流出過程の解明に向けた検討状況

    北村成寿

    宇宙空間からの地球超高層大気観測に関する研究会  2019.9.12 

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    Event date： 2019.9

    Language：Japanese   Presentation type：Oral presentation (general)  

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  49. Solar Zenith Angle Dependence of Relationship Between Energy Inputs to the Ionosphere and Ion Outflow Fluxes

    Naritoshi Kitamura

    2019 GEM Summer Workshop  2019.6.27 

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    Event date： 2019.6

    Language：English   Presentation type：Poster presentation  

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  50. Small scale whistler mode waves near the magnetic field intensity minimum in the magnetosheath

    Naritoshi Kitamura

    JpGU meeting 2019  2019.5.29 

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    Event date： 2019.5

    Language：English   Presentation type：Poster presentation  

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  51. 地球磁気圏探査 (地球電離圏からのイオン流出)

    北村成寿

    電離圏・磁気圏探査衛星検討リサーチグループ最終会合 -STP分野のロードマップ作成に向けて  2019.3.29 

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    Event date： 2019.3

    Language：Japanese   Presentation type：Oral presentation (general)  

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  52. Upflow/Outflowの人工衛星観測

    北村成寿

    名古屋大学宇宙地球環境研究所 研究集会 「極域電離圏における電離大気流出現象のメカニズム解明を目指した戦略的研究」  2019.3.28 

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    Event date： 2019.3

    Language：Japanese   Presentation type：Oral presentation (general)  

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  53. Direct Measurements of Energy Transfer from Hot Protons to EMIC Waves Observed by MMS during Pc5 Waves in the Outer Magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    AGU fall meeting 2018  2018.12.12 

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    Event date： 2018.12

    Language：English   Presentation type：Oral presentation (general)  

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  54. Observation of whistler mode waves near the local minimum of magnetic field intensity in the magnetosheath mirror structures International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting  2018.11.27 

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    Event date： 2018.11

    Language：Japanese   Presentation type：Oral presentation (general)  

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  55. Direct measurements of energy transfer from hot H+ to EMIC waves by MMS International coauthorship International conference

    Naritoshi Kitamura

    2018 GEM Summer Workshop  2018.6.18 

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    Event date： 2018.6

    Language：English   Presentation type：Oral presentation (general)  

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  56. Direct measurements of two-way energy transfer between EMIC waves and ions observed by the MMS spacecraft in the outer magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    2018 GEM Summer Workshop  2018.6.19 

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    Event date： 2018.6

    Language：English   Presentation type：Poster presentation  

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  57. In-situ Observation Plans in Next Japanese Space Exploration Mission(FACTORS) for Ion Acceleration/Heating Processes in the Terrestrial Magnetosphere-Ionosphere Coupling System International conference

    Naritoshi Kitamura

    2018 GEM summer workshop  2018.6.21 

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    Event date： 2018.6

    Language：English   Presentation type：Oral presentation (general)  

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  58. Non-resonant acceleration of He+ by EMIC waves observed by MMS in the magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    JpGU meeting 2018  2018.5.21 

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    Event date： 2018.5

    Language：English   Presentation type：Poster presentation  

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  59. Direct evidence of energy exchange between EMIC waves and ions observed by the MMS spacecraft at the off-equator magnetosphere International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting 2016  2016.11.20 

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    Language：Japanese   Presentation type：Poster presentation  

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  60. Direct Measurements of Energy Transfer between Hot Protons and He+ via EMIC Waves Observed by MMS in the Outer Magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    AGU fall meeting 2017  2017.12.7 

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    Language：English   Presentation type：Oral presentation (general)  

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  61. Direct measurements of energy exchange between EMIC waves and ions observed by the MMS spacecraft in the magnetosphere Invited International coauthorship International conference

    Naritoshi Kitamura

    JpGU-AGU joint meeting 2017  2017.5.20 

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

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  62. Direct measurements of energy exchange between EMIC waves and ions in the magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    MMS 2nd Science Community Workshop  2017.6.8 

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  63. First direct measurements of energy exchange rates between EMIC waves and ions (hot H+ and cold He+) in the magnetosphere by cyclotron resonance and non-resonant interaction International coauthorship

    Naritoshi Kitamura

    2017.1.31 

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    Language：Japanese   Presentation type：Oral presentation (general)  

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  64. 波動粒子相互作用直接計測(WPIA)による電磁イオンサイクロトロン(EMIC)波動とイオンの相互作用領域の同定 International coauthorship

    北村成寿

    実験室・宇宙プラズマ研究会「乱流・輸送・粒子加速」  2017.12.7 

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    Language：Japanese   Presentation type：Oral presentation (general)  

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  65. 極域イオン流出に関連する波動粒子相互作用、MMS衛星による波動の複数点観測から明らかになった課題

    北村成寿

    名古屋大学宇宙地球環境研究所 研究集会「宇宙惑星結合系の包括的理解と将来探査計画 ～地球、系内・系外惑星における超高層大気・外気圏の融合的研究の創設に向けて～」  2019.3.29 

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  66. 極域イオン流出に関連する波動粒子相互作用

    北村成寿

    名古屋大学宇宙地球環境研究所 研究集会 「極域電離圏における電離大気流出現象のメカニズム解明に向けた戦略的観測計画」  2018.3.7 

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  67. 地球電離圏からのイオン流出 International coauthorship

    北村成寿

    名古屋大学宇宙地球環境研究所 研究集会 「宇宙惑星結合系科学の実証的研究の創設に向けて」  2016.12.26 

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  68. 人工衛星で観測される大気流出

    北村成寿

    国立極地研究所 研究集会 「EISCAT レーダー・地上光学観測・観測ロケットによるカスプ近傍電離大気流出現象のメカニズ ム解明に向けた総合観測」  2017.7.7 

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  69. Shift of the magnetopause reconnection line to the winter hemisphere under southward IMF conditions: Geotail and MMS observations International coauthorship International conference

    Naritoshi Kitamura

    AGU fall meeting 2016  2016.12.13 

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  70. Shift of the magnetopause reconnection line to the winter hemisphere under southward IMF conditions: Geotail and MMS observations International coauthorship International conference

    Naritoshi Kitamura

    GEM-CEDAR workshop 2016  2016.6.22 

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    Language：English   Presentation type：Poster presentation  

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  71. Shift of the magnetopause reconnection line to the winter hemisphere under southward IMF conditions: Geotail and MMS observations International coauthorship International conference

    Naritoshi Kitamura

    JpGU meeting 2016  2016.5.24 

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    Language：English   Presentation type：Oral presentation (general)  

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  72. Overview of 2015-11-18 Geotail-MMS conjunction event International coauthorship International conference

    Naritoshi Kitamura

    GEM-CEDAR workshop 2016  2016.6.23 

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    Language：English   Presentation type：Oral presentation (general)  

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  73. Observations of wave-particle (EMIC wave and protons) interactions in the outer magnetosphere International coauthorship International conference

    Naritoshi Kitamura

    MMS SWT meeting  2018.2.27 

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  74. Model and Measurement Comparison of Ion Outflow International coauthorship International conference

    Naritoshi Kitamura

    GEM-CEDAR workshop 2016  2016.6.24 

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  75. MMS衛星観測データを用いた外部磁気圏におけるイオンとEMIC波動間のエネルギー輸送の直接計測

    北村成寿

    磁気圏ダイナミクス研究会  2018.3.20 

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    Language：Japanese   Presentation type：Oral presentation (general)  

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  76. Direct measurements of energy transfer from hot protons to EMIC waves observed by MMS during Pc5 waves in the outer magnetosphere International coauthorship

    Naritoshi Kitamura

    SGEPSS fall meeting 2017  2017.10.19 

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    Language：Japanese   Presentation type：Oral presentation (general)  

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  77. MMS衛星によって磁気圏外周部で観測されたEMIC波によるHe+イオン加速イベント

    北村成寿

    太陽惑星系宇宙プラズマ​中の重イオンに関する研究集会  2017.3.8 

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  78. MMS(Magnetospheric Multi-Scale mission)衛星群の観測

    北村成寿

    サブストーム研究会  2017.1.25 

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▼display all

To the head of Presentations.▲

KAKENHI (Grants-in-Aid for Scientific Research) 4

  1. 波動粒子相互作用直接解析手法を用いた電磁サイクロトロン波動と粒子の相互作用の研究

    Grant number：23K03476  2023.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    北村 成寿

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    Authorship：Principal investigator  Grant type：Competitive

    Grant amount：\4550000 （ Direct Cost: \3500000 、 Indirect Cost：\1050000 ）

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  2. FAST衛星の長期観測データを用いた地球極域からのイオン流出、イオン加速の研究

    Grant number：19K14781  2019.4 - 2025.3

    日本学術振興会  科学研究費助成事業  若手研究

    北村 成寿

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    Authorship：Principal investigator  Grant type：Competitive

    Grant amount：\2860000 （ Direct Cost: \2200000 、 Indirect Cost：\660000 ）

    将来の戦略的小型衛星計画として提案予定のFACTORS衛星計画による地球からのイオン流出過程(特に波動によるイオン加速過程)の詳細研究を見据え、まずは地球極域からの顕著なイオン流出がどのような条件でどの種類のエネルギー流入に伴って発生するか明らかにするためにFAST衛星のデータ解析を推進している。FAST衛星の1998年付近の遠地点付近(高度3000-4100 km)のイオン、電子、電磁場のフラックスについての統計解析を行った結果(大フラックスのイオン流出は日陰時にはほとんど起こらない事及び電離圏へのエネルギーインプットとイオン流出フラックスの経験的関係式)について、オープンアクセスであるEarth Planets and Space誌に前年度終わりに投稿した論文について、査読結果に基づく改訂や結果の再チェック等を推進し、受理された。この統計解析では、約1年程度のイオン種の区別は無いデータを用いて解析を行ったが、新たにイオン種を区別したデータについて長期にわたって較正が終了したという連絡があり、使用が可能になった。この為、特に酸素イオン流出に着目できるように新たな解析プログラムの準備や新たな期間でのイベント選定を進めている。
    戦略的小型衛星計画の公募が2022年度にずれ込むことが決まったため、FACTORS衛星計画の提案書のための検討を更に推進した。特に、ロケット性能等の制約で遠地点高度を4000 kmから3500 km程度まで低下させる事が許容されるかについてFAST衛星の過去のデータをチェックし、十分許容できそうであるという結果を得た。

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  3. 電離圏からのイオン流出過程と地球起源イオンのリングカレントへの寄与に関する研究

    Grant number：12J05283  2012.4 - 2015.3

    日本学術振興会  科学研究費助成事業  特別研究員奨励費

    北村 成寿

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    Authorship：Principal investigator  Grant type：Competitive

    Grant amount：\3960000 （ Direct Cost: \3600000 、 Indirect Cost：\360000 ）

    オーロラ帯では磁気圏からのエネルギー流入によってイオン流出が発生し、磁気圏に地球起源イオンを供給している。特に、重い酸素イオンの流出及び磁気圏への供給に関してはこのオーロラ帯からのイオン流出の寄与が大きく、重要視されている。FAST衛星の1998年1月から1999年2月の電磁場、電子、イオン、イオン組成のデータを解析し、流出するイオンの組成、エネルギーインプットと流出イオンフラックスの太陽天頂角依存性について解析を行った。その結果、磁力線のフットプリントの電離圏が日照状態の場合には流出イオンは酸素イオンが支配的な傾向があるが、日陰では水素イオンが支配的な傾向があることが明らかになった。また、大フラックスの酸素イオン流出イベントについては主に日照時に発生していた。降り込み電子(>50 eV)の密度とイオン流出フラックスの関係についても太陽天頂角依存性が見られ、酸素イオンの流出フラックスの理解には以前から指摘されていたエネルギーインプットに加えて、電離圏への日照の効果を考慮する事が重要である事を示した。
    このデータセットを用いてイオン組成比(酸素/水素、ヘリウム/水素)の太陽天頂角依存性、エネルギーインプット(ポインティングフラックス、電子降り込み)とイオン流出フラックスの経験モデルを構築した。これらの経験モデルは磁気圏のモデリング研究において地球起源イオンの地球側の境界条件の設定に不可欠である。既存の経験モデルではイオン組成、太陽天頂角の効果が全く考慮されていなかった。過去の研究では特に日陰での酸素イオンの流出量を過大評価していた可能性があることが示された。新たに構築した経験モデルは地球起源イオンのリングカレントへの寄与についてのより定量的な評価に大きく寄与し、磁気嵐の発達過程の理解へも貢献することができると期待される。

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  4. 極域電離圏―磁気圏結合系におけるプラズマ密度構造と磁気嵐に伴う変動

    Grant number：10J01671  2010.4 - 2012.3

    日本学術振興会  科学研究費助成事業  特別研究員奨励費

    北村 成寿

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    Authorship：Principal investigator  Grant type：Competitive

    Grant amount：\1400000 （ Direct Cost: \1400000 ）

    極域電離圏は、そこから伸びる磁力線が地球磁気圏の外側や惑星間空間に接続しており、磁力線に沿ってプラズマが流出していく。磁気圏の尾部に輸送されたプラズマは内部磁気圏のエネルギーの高いプラズマの源となるため、極域電離圏は磁気圏全体のプラズマの源として重要な領域である。
    あけぼの衛星、Intercosmos衛星、EISCATスバールバルレーダーのデータを用いて、地磁気静穏時の極冠域電離圏-磁気圏での電子密度分布、電子温度、イオン温度の太陽天頂角依存性を明らかにし、電離圏への日照の有無がこれらのパラメータに極めて強い影響を与えていることを明らかにした。さらに、電離圏が日照状態の場合について、過去のモデル計算でイオン流出への重要性が指摘されている光電子に着目し、FAST衛星の観測データを解析した。その結果、地磁気静穏時には磁力線に沿って電位差が存在し、電離圏から流出する光電子を減速、反射していることを観測的に示した。高高度で反射されてくる光電子のエネルギーの解析から、典型的な電位差は20V程度であり、過去のモデルによる予測よりは小さいものの、高高度に大きな電位差の存在を予測したタイプのモデルが静穏時の極冠域電離圏からのイオンの流出の描像として比較的妥当であるという結果を得た。
    一方、磁気嵐時のイオン流出については、あけぼの衛星が電子密度増加を観測し、ほぼ同時にPolar衛星がイオン上昇流を観測している2000年4月6日から7日にかけての同時観測データを解析し、磁気嵐中の電子密度増加の発生時に磁気圏へ流出できるエネルギーをもったイオン上昇流の見られる領域は、高度9000km付近の極域磁気圏においてはカスプから昼側極冠内に昼夜方向に10°程度も広がっていることを明らかにした。これは、磁気嵐時の磁気圏への重イオンの供給に関して、極域磁気圏においての昼側極冠域の重要性を示している。

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Social Contribution 3

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    Role(s)：Lecturer

    東京都立富士高等学校・附属中学校  2020.1

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    Type：Visiting lecture

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  2. STEPLE出前授業 in半田空の科学館

    Role(s)：Demonstrator

    半田空の科学館  2014.9

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    Type：Visiting lecture

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  3. 大学・大学院ってどんなところ？～宇宙と地球のつながり～

    Role(s)：Lecturer

    信州大学教育学部附属長野中学校  2013.2

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    Type：Visiting lecture

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