Updated on 2026/11/02

Information

 

写真a

 
IJUIN TAKUYA
 
Organization
International Center for Space and Planetary Environmental Science Assistant Professor
Title
Assistant Professor
Contact information
メールアドレス
External link

Research Areas

  • Natural Science / Space and planetary sciences

Degree

  • 博士(理学) （ 2026.3 Kyushu University ）

Education

  • Kyushu University   理学府   地球惑星科学専攻

    2023.4 - 2026.3

    　 More details

    Country：Japan

Research Interests・Research Keywords

  • Research theme： Three-dimensional structure of ionospheric current system

    Keyword： ionosphere

    Research period： 2020.10 - Present

Awards

  • JpGU2024 宇宙惑星科学セクション 学生優秀発表賞

    2024.7   日本地球惑星科学連合   Sq-EEJ電流系の3次元構造の解明: GAIAの電気力学モデルを用いた分極効果の寄与の調査

    　More details

    Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Papers

  • Global Cowling Effects in the Sq‐EEJ Current System Under Electrostatic Approximation: Theoretical Simulation Reviewed International journal

    T. Ijuin, H. Jin, A. Yoshikawa

    Geophysical Research Letters   53 ( 16 )   2026.8   （ ISSN:0094-8276 eISSN:1944-8007 ）

    　More details

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

    Abstract

    The solar quiet (Sq) current and equatorial electrojet are widely known as one of the fundamental currents in ionosphere. Although the Sq‐EEJ current system has been extensively investigated, the manner in which Hall and Pedersen current components collectively organize the system has not been clearly described. To examine this, we perform a quasi‐three‐dimensional numerical simulation using the electrodynamics component of the GAIA model with a simplified neutral wind and a tilted dipole magnetic field. By applying a Hall polarization field separation method, we show that the Cowling effect operates globally through complementary roles of Pedersen and Hall currents: the primary field Pedersen and secondary field Hall currents enhance the Sq‐EEJ system, while the primary Hall and secondary Pedersen currents provide compensating closure. This component‐resolved description clarifies the physical basis of the Sq‐EEJ current system and advances understanding of ionospheric electrodynamics.

    DOI： 10.1029/2026GL123547

    Web of Science

    Scopus

    researchmap

    Other Link： https://agupubs.onlinelibrary.wiley.com/doi/full-xml/10.1029/2026GL123547

Presentations

  • Joule Heating of Sq-EEJ Current System in Three-dimensional Ionosphere with GAIA International conference

    Takuya Ijuin, Akimasa Yoshikawa

    Asia Oceania Geosciences Society  2026.8 

    　More details

    Event date： 2026.8

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Three-dimensional global ionospheric current structure under the presence of Region-2 field-aligned currents

    Takuya Ijuin, Akimasa Yoshikawa

    JpGU-AGU Joint Meeting 2026  2026.5 

    　More details

    Event date： 2026.5

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • MAGDAS: The Global Geomagnetic Observation Network, and Its Applications in Space Weather International conference

    Shuji Abe, Kirolosse Girgis, Akiko Fujimoto, Akihiro Ikeda, Teiji UozumiYuki Obana, Takuya Ijuin, Akimasa Yoshikawa

    Asia Oceania Geosciences Society  2026.8 

    　More details

    Event date： 2026.8

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Current Status and Future Prospects of MAGDAS Project

    Shuji Abe, Kirolosse M. Girgis, Akiko Fujimoto, Akihiro Ikeda, Teiji Uozumi, Yuki Obana, Takuya Ijuin, Akimasa Yoshikawa

    JpGU-AGU Joint Meeting 2026  2026.5 

    　More details

    Event date： 2026.5

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Toward REPPU–GAIA Coupling: Current Status and Outstanding Issues

    Aoi Nakamizo, Akimasa Yoshikawa, Takuya Ijuin, Hidekatsu Jin, Keiichiro Fukazawa, Chihiro Tao, Hitoshi Fujiwara, Yasunobu Miyoshi

    JpGU-AGU Joint Meeting 2026  2026.5 

    　More details

    Event date： 2026.5

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Three-dimensional structure and causality of global ionospheric currents triggered by Region-1 FAC

    Takuya Ijuin, Akimasa Yoshikawa

    SGEPSS2025  2025.11 

    　More details

    Event date： 2025.11

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • Three-dimensional structure of ionospheric global current system driven by M-I coupling

    Takuya Ijuin, Akimasa Yoshikawa

    JpGU2025  2025.5 

    　More details

    Event date： 2025.5

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • The three-dimensional structure of Sq-EEJ current system: The role of polarization effects utilizing the electrodynamics component of GAIA

    Takuya Ijuin, Akimasa Yoshikawa, Yasunobu Miyoshi

    AGU annual meeting 2024  2024.12 

    　More details

    Event date： 2024.12

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Elucidating the three-dimensional Sq-EEJ current system: The role of polarization effects utilizing the GAIA electrodynamics component

    Takuya Ijuin, Akimasa Yoshikawa, Yasunobu Miyoshi

    JpGU2024  2024.5 

    　More details

    Event date： 2024.5

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • Educational Activities for Young Researchers in Kyushu University’s MAGDAS Project

    Shuji Abe, Akihiro Ikeda, Akiko Fujimoto, Teiji Uozumi, Yuki Obana, Kirolosse Girgis, Moe Hayashi, Kumi Takayama, Takuya Ijuin, Akimasa Yoshikawa

    International Symposium on Data Science (DSWS-2023) -Building an Open-Data Collaborative Network in the Asia-Oceania Area -  2023.12 

    　More details

    Event date： 2023.12

    Presentation type：Poster presentation  

    researchmap

  • Introduction of educational activities related to space weather at i-SPES, Japan

    Shuji Abe, Akihiro Ikeda, Akiko Fujimoto, Teiji Uozumi, Yuki Obana, Kirolosse Girgis, Moe Hayashi, Kumi Takayama, Takuya Ijuin, Akimasa Yoshiakawa

    AOSWA2023  2023.10 

    　More details

    Event date： 2023.10

    Presentation type：Oral presentation (general)  

    researchmap

  • Analysis of EEJ structure in M-I coupling system using IGRF model and quasi-three-dimensional potential solver

    Takuya Ijuin, Akimasa Yoshikawa, Yasunobu Miyoshi, Yukihiro Shinagawa, Hitoshi Fujiwara, Hidekatsu Jin, Aoi Nakamizo, Chihiro Tao, Kazuo Shiokawa

    SGEPSS2022  2022.11 

    　More details

    Event date： 2022.11

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • Global Geomagnetic Observations and International Collaboration through the MAGDAS Project

    Shuji Abe, Kirolosse Girgis, Akiko Fujimoto, Akihiro Ikeda, Teiji Uozumi, Yuki Obana, Takuya Ijuin, Akimasa Yoshikawa

    The XXIst IAGA Workshop on Geomagnetic Observatory Instruments, Data Acquisition and Processing  2026.10 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

▼display all