Basic Information

Affiliated programs (koza)

• Graduate School of Science, 物理学・宇宙物理学専攻 理論天体物理学講座, 教授

Faculty

• 理学部

Professional Memberships

• From Sep. 2012, To Present

  International Astronomical Union
• From 1994, To Present

  Astronomical Society of Japan

Academic Degree

• 博士（理学）(総合研究大学院大学)
• 修士（工学）(京都大学)

ID,URL

• J-Global ID

  202101012182280587

• Researcher number

  00311184

researchmap URL

• https://researchmap.jp/yokoyama.takaaki

Research

Research Interests

• astronomical plasma
• magnetohydrodynamics
• plasma
• Sun
• stellar physics

Research Areas

• Natural sciences, Astronomy, 太陽天体プラズマ物理学

Papers

• Conditions for Solar Prominence Formation Triggered by Single Localized Heating

  Takero Yoshihisa; Takaaki Yokoyama; Takafumi Kaneko

  The Astrophysical Journal, 27 Dec. 2024

  
• MHD simulation of solar coronal X-ray jets - Emerging flux reconnection model

  Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Letters and Communications, 1996

  
• A two-dimensional magnetohydrodynamic simulation of chromospheric evaporation in a solar flare based on a magnetic reconnection model

  Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Journal, 1998

  
• Magnetic reconnection coupled with heat conduction

  Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Journal, 1997

  
• Numerical simulation of magnetic reconnection in eruptive flares

  Tetsuya Magara; Shin Mineshige; Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Journal, 1996

  
• Coronal X-ray jets observed with the Yohkoh soft X-ray telescope

  Kazunari Shibata; Takaaki Yokoyama; Masumi Shimojo

  Earth, Planets and Space, 1996

  
• Magnetohydrodynamic simulation of a solar flare with chromospheric evaporation effect based on the magnetic reconnection model

  Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Journal, 10 Mar. 2001

  
• A unified model of coronal mass ejection-related type II radio bursts

  Tetsuya Magara; Pengfei Chen; Kazunari Shibata; Takaaki Yokoyama

  Astrophysical Journal, 01 Aug. 2000

  
• Origin of the universal correlation between the flare temperature and the emission measure for solar and stellar flares

  Kazunari Shibata; Takaaki Yokoyama

  Astrophysical Journal, 20 Nov. 1999

  
• Nonlinear reflection process of linearly-polarized, broadband Alfvén waves in the fast solar wind

  Munehito Shoda; Takaaki Yokoyama

  11 Feb. 2016, Peer-reviewed

  
• Magnetic Tornado Properties: A Substantial Contribution to the Solar Coronal Heating via Efficient Energy Transfer

  Hidetaka Kuniyoshi; Munehito Shoda; Haruhisa Iijima; Takaaki Yokoyama

  The Astrophysical Journal, 01 May 2023

  
• APPARENT CROSS-FIELD SUPERSLOW PROPAGATION OF MAGNETOHYDRODYNAMIC WAVES IN SOLAR PLASMAS

  T. Kaneko; M. Goossens; R. Soler; J. Terradas; T. Van Doorsselaere; T. Yokoyama; A. N. Wright

  ASTROPHYSICAL JOURNAL, Oct. 2015, Peer-reviewed

  
• Magnetohydrodynamic simulation of solar coronal chromospheric evaporation jets caused by magnetic reconnection associated with magnetic flux emergence

  T Miyagoshi; T Yokoyama

  ASTROPHYSICAL JOURNAL, Oct. 2004, Peer-reviewed

  
• Magnetohydrodynamic numerical simulations of solar X-ray jets based on the magnetic reconnection model that includes chromospheric evaporation

  T Miyagoshi; T Yokoyama

  ASTROPHYSICAL JOURNAL, Aug. 2003, Peer-reviewed

  
• Fast Magnetic Wave Could Heat the Solar Low-beta Chromosphere

  Yikang Wang; Takaaki Yokoyama; Haruhisa Iijima

  The Astrophysical Journal Letters, 01 Aug. 2021, Peer-reviewed

  
• Magnetic flux cancellation associated with a recurring solar jet observed with Hinode, RHESSI, and STEREO/EUVI

  C. Chifor; H. Isobe; H. E. Mason; I. G. Hannah; P. R. Young; G. Del Zanna; S. Krucker; K. Ichimoto; Y. Katsukawa; T. Yokoyama

  ASTRONOMY & ASTROPHYSICS, Nov. 2008, Peer-reviewed

  
• One solar-cycle observations of prominence activities using the Nobeyama Radioheliograph 1992-2004

  M Shimojo; T Yokoyama; A Asai; H Nakajima; K Shibasaki

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Feb. 2006, Peer-reviewed

  
• The nonlinear alfvén wave model for solar coronal heating and nanoflares

  Satoshi Moriyasu; Takahiro Kudoh; Takaaki Yokoyama; Kazunari Shibata

  Astrophysical Journal, 20 Jan. 2004

  
• Magnetic reconnection triggered by the Parker instability in the galaxy: Two-dimensional numerical magnetohydrodynamic simulations and application to the origin of X-ray gas in the Galactic halo

  Syuniti Tanuma; Takaaki Yokoyama; Takahiro Kudoh; Kazunari Shibata

  Astrophysical Journal, 01 Jan. 2003, Peer-reviewed

  
• Difference between spatial distributions of the H alpha kernels and hard X-ray sources in a solar flare

  A Asai; S Masuda; T Yokoyama; M Shimojo; H Isobe; H Kurokawa; K Shibata

  ASTROPHYSICAL JOURNAL, Oct. 2002, Peer-reviewed

  
• The Solar-C_EUVST mission: the latest status

  Toshifumi Shimizu; Shinsuke Imada; Tomoko Kawate; Yoshinori Suematsu; Hirohisa Hara; Toshihiro Tsuzuki; Yukio Katsukawa; Masahito Kubo; Ryoko Ishikawa; Tetsuya Watanabe; Shin Toriumi; Kiyoshi Ichimoto; Shin'ichi Nagata; Takahiro Hasegawa; Takaaki Yokoyama; Kyoko Watanabe; Katsuhiko Tsuno; Clarence M. Korendyke; Harry P. Warren; Bart De Pontieu; Paul Boerner; Sami K. Solanki; Luca Teriaca; Udo Schühle; Sarah Matthews; David Long; William Thomas; Barry Hancock; Hamish Reid; Andrzej Fludra; Frederic Auchere; Vincenzo Andretta; Giampiero Naletto; Luca Poletto; Louise Harra

  Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray, 13 Dec. 2020

  
• Inverse First Ionization Potential Effects in Giant Solar Flares Found from Earth X-Ray Albedo with Suzaku/XIS

  Satoru Katsuda; Masanori Ohno; Koji Mori; Tatsuhiko Beppu; Yoshiaki Kanemaru; Makoto S. Tashiro; Yukikatsu Terada; Kosuke Sato; Kae Morita; Hikari Sagara; Futa Ogawa; Haruya Takahashi; Hiroshi Murakami; Masayoshi Nobukawa; Hiroshi Tsunemi; Kiyoshi Hayashida; Hironori Matsumoto; Hirofumi Noda; Hiroshi Nakajima; Yuichiro Ezoe; Yohko Tsuboi; Yoshitomo Maeda; Takaaki Yokoyama; Noriyuki Narukage

  ASTROPHYSICAL JOURNAL, Mar. 2020

  
• Simulation of Alfven Wave Propagation in the Magnetic Chromosphere with Radiative Loss: Effects of Nonlinear Mode Coupling on Chromospheric Heating

  Yikang Wang; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Mar. 2020

  
• Estimating the Temperature and Density of a Spicule from 100 GHz Data Obtained with ALMA

  Masumi Shimojo; Tomoko Kawate; Takenori J. Okamoto; Takaaki Yokoyama; Noriyuki Narukagel; Taro Sakao; Kazumasa Iwai; Gregory D. Fleishman; Gazunari Shibatas

  ASTROPHYSICAL JOURNAL LETTERS, Jan. 2020

  
• Three-dimensional Simulation of the Fast Solar Wind Driven by Compressible Magnetohydrodynamic Turbulence

  Munehito Shoda; Takeru Ken Suzuki; Mahboubeh Asgari-Targhi; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL LETTERS, Jul. 2019

  
• Diffusion regions and 3D energy mode development in spontaneous reconnection

  Shuoyang Wang; Takaaki Yokoyama

  PHYSICS OF PLASMAS, Jul. 2019

  
• Observations of photospheric magnetic structure below a dark filament using the Hinode Spectro-Polarimeter

  Takaaki Yokoyama; Yukio Katsukawa; Masumi Shimojo

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Apr. 2019

  
• The Solar-C_EUVST mission

  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 Warren; Ted Tarbell; Bart De Pontieu; Sami Solanki; Luca Teriaca; Udo Schuehle; Louise Harra; Sarah Matthews; A. Fludra; F. Auchere; V. Andretta; G. Naletto; A. Zhukov

  UV, X-RAY, AND GAMMA-RAY SPACE INSTRUMENTATION FOR ASTRONOMY XXI, 2019

  
• Impact of Dynamic State on the Mass Condensation Rate of Solar Prominences

  Takafumi Kaneko; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Dec. 2018

  
• ALMA Observations of the Solar Chromosphere on the Polar Limb

  Takaaki Yokoyama; Masumi Shimojo; Takenori J. Okamoto; Haruhisa Iijima

  ASTROPHYSICAL JOURNAL, Aug. 2018

  
• Anisotropic Magnetohydrodynamic Turbulence Driven by Parametric Decay Instability: The Onset of Phase Mixing and Alfven Wave Turbulence

  Munehito Shoda; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL LETTERS, Jun. 2018

  
• Frequency-dependent Alfven-wave Propagation in the Solar Wind: Onset and Suppression of Parametric Decay Instability

  Munehito Shoda; Takaaki Yokoyama; Takeru K. Suzuki

  ASTROPHYSICAL JOURNAL, Jun. 2018

  
• A Self-consistent Model of the Coronal Heating and Solar Wind Acceleration Including Compressible and Incompressible Heating Processes

  Munehito Shoda; Takaaki Yokoyama; Takeru K. Suzuki

  ASTROPHYSICAL JOURNAL, Feb. 2018

  
• High-frequency Spicule Oscillations Generated via Mode Conversion

  Munehito Shoda; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Feb. 2018

  
• Reconnection-Condensation Model for Solar Prominence Formation

  Takafumi Kaneko; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Aug. 2017

  
• Non-kinematic Flux-transport Dynamos Including the Effects of Diffusivity Quenching

  Chiaki Ichimura; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Apr. 2017

  
• THREE-DIMENSIONAL MHD MAGNETIC RECONNECTION SIMULATIONS WITH A FINITE GUIDE FIELD: PROPOSAL OF THE SHOCK-EVOKING POSITIVE-FEEDBACK MODEL

  Shuoyang Wang; Takaaki Yokoyama; Hiroaki Isobe

  ASTROPHYSICAL JOURNAL, Sep. 2015

  
• RESONANT ABSORPTION OF TRANSVERSE OSCILLATIONS AND ASSOCIATED HEATING IN A SOLAR PROMINENCE. I. OBSERVATIONAL ASPECTS

  Takenori J. Okamoto; Patrick Antolin; Bart de Pontieu; Han Uitenbroek; Tom van Doorsselaere; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Aug. 2015

  
• SIMULATION STUDY OF SOLAR PLASMA ERUPTIONS CAUSED BY INTERACTIONS BETWEEN EMERGING FLUX AND CORONAL ARCADE FIELDS

  Takafumi Kaneko; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Nov. 2014

  
• STATISTICAL ANALYSIS OF THE HORIZONTAL DIVERGENT FLOW IN EMERGING SOLAR ACTIVE REGIONS

  Shin Toriumi; Keiji Hayashi; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Oct. 2014

  
• PROBING THE SHALLOW CONVECTION ZONE: RISING MOTION OF SUBSURFACE MAGNETIC FIELDS IN THE SOLAR ACTIVE REGION

  Shin Toriumi; Stathis Ilonidis; Takashi Sekii; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL LETTERS, Jun. 2013

  
• TEMPORAL AND SPATIAL ANALYSES OF SPECTRAL INDICES OF NONTHERMAL EMISSIONS DERIVED FROM HARD X-RAYS AND MICROWAVES

  Ayumi Asai; Junko Kiyohara; Hiroyuki Takasaki; Noriyuki Narukage; Takaaki Yokoyama; Satoshi Masuda; Masumi Shimojo; Hiroshi Nakajima

  ASTROPHYSICAL JOURNAL, Feb. 2013

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• Numerical Simulation and SOT Magnetogram Analysis of the Small-scale Magnetic Elements in a Solar Emerging Flux Region

  Shin Toriumi; Takaaki Yokoyama

  FIFTH HINODE SCIENCE MEETING: EXPLORING THE ACTIVE SUN, 2012

  
• Numerical Experiments on the Two-Step Emergence of Solar Magnetic Fields from the Convective Layer

  Shin Toriumi; Takaaki Yokoyama

  HINODE-3: THE 3RD HINODE SCIENCE MEETING, 2012

  
• Dependence of the Magnetic Energy of Solar Active Regions on the Twist Intensity of the Initial Flux Tubes

  Shin Toriumi; Takehiro Miyagoshi; Takaaki Yokoyama; Hiroaki Isobe; Kazunari Shibata

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Apr. 2011

  
• Generation of Alfven Waves by Magnetic Reconnection

  Hiromitsu Kigure; Kunio Takahashi; Kazunari Shibata; Takaaki Yokoyama; Satoshi Nozawa

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Aug. 2010

  
• PROMINENCE FORMATION ASSOCIATED WITH AN EMERGING HELICAL FLUX ROPE

  Takenori J. Okamoto; Saku Tsuneta; Bruce W. Lites; Masahito Kubo; Takaaki Yokoyama; Thomas E. Berger; Kiyoshi Ichimoto; Yukio Katsukawa; Shin'ichi Nagata; Kazunari Shibata; Toshifumi Shimizu; Richard A. Shine; Yoshinori Suematsu; Theodore D. Tarbell; Alan M. Title

  ASTROPHYSICAL JOURNAL, May 2009

  
• IMAGING SPECTROSCOPY ON PREFLARE CORONAL NONTHERMAL SOURCES ASSOCIATED WITH THE 2002 JULY 23 FLARE

  Ayumi Asai; Hiroshi Nakajima; Masumi Shimojo; Takaaki Yokoyama; Satoshi Masuda; Saem Krucker

  ASTROPHYSICAL JOURNAL, Apr. 2009

  
• Formation of solar magnetic flux tubes with kilogauss field strength induced by convective instability

  Shin'ichi Nagata; Saku Tsuneta; Yoshinori Suematsu; Kiyoshi Ichimoto; Yukio Katsukawa; Toshifumi Shimizu; Takaaki Yokoyama; Theodore D. Tarbell; Bruce W. Lites; Richard A. Shine; Thomas E. Berger; Alan M. Title; Luis R. Bellot Rubio; David Orozco Suares

  ASTROPHYSICAL JOURNAL LETTERS, Apr. 2008

  
• Emergence of a helical flux rope under an active region prominence

  Takenori J. Okamoto; Saku Tsuneta; Bruce W. Lites; Masahito Kubo; Takaaki Yokoyama; Thomas E. Berger; Kiyoshi Ichimoto; Yukio Katsukawa; Shin'ichi Nagata; Kazunari Shibata; Toshifumi Shimizu; Richard A. Shine; Yoshinori Suematsu; Theodore D. Tarbell; Alan M. Title

  ASTROPHYSICAL JOURNAL LETTERS, Feb. 2008

  
• Active Region Microflares From Hinode and RHESSI

  Cristina Chifor; Iain G. Hannah; Helen E. Mason; Hiroaki Isobe; Takaaki Yokoyama; Peter R. Young; Durgesh Tripathi

  FIRST RESULTS FROM HINODE, 2008

  
• Initial results on line-of-sight field calibrations of SP/NFI data taken by SOT/Hinode

  Jongchul Chae; Yong-Jae Moon; Young-Deuk Park; Kiyoshi Ichimoto; Takashi Sakurai; Yoshinori Suematsu; Saku Tsuneta; Yukio Katsukawa; Toshifumi Shimizu; Richard A. Shine; Theodore D. Tarbell; Alan M. Title; Bruce Lites; Masahito Kubo; Shin'ichi Nagata; Takaaki Yokoyama

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Nov. 2007

  
• Fine-scale structures of the evershed effect observed by the Solar Optical Telescope aboard Hinode

  Kiyoshi Ichimoto; Richard A. Shine; Bruce Lites; Masahitc Kubo; Toshifumi Shimizu; Yoshinori Suematsu; Saku Tsuneta; Yukio Katsukawa; Theodore D. Tarbell; Alan M. Title; Shin'ichi Nagata; Takaaki Yokoyama; Masumi Shimojo

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Nov. 2007

  
• Formation process of a light bridge revealed with the Hinode Solar Optical Telescope

  Yukio Katsukawa; Takaaki Yokoyama; Thomas E. Berger; Kiyoshi Ichimoto; Masahito Kubo; Bruce Lites; Shin'ichi Nagata; Toshifumi Shimizu; Richard A. Shine; Yoshinori Suematsu; Theodore D. Tarbell; Alan M. Title; Saku Tsuneta

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Nov. 2007

  
• Hinode observations of a vector magnetic field change associated with a flare on 2006 December 13

  Masahito Kubo; Takaaki Yokoyama; Yukio Katsukawa; Bruce Lites; Saku Tsuneta; Yoshinori Suematsu; Kiyoshi Ichimoto; Toshifumi Shimizu; Shin'ichi Nagata; Theodore D. Tarbell; Richard A. Shine; Alan M. Title; David Elmore

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Nov. 2007

  
• Hinode SP vector magnetogram of AR 10930 and its cross-comparison with MDI

  Yong-Jae Moon; Yeon-Han Kim; Young-Deuk Park; Kiyoshi Ichimoto; Takashi Sakurai; Jongchul Chae; Kyung Suk Cho; Suchan Bong; Yoshinori Suematsu; Saku Tsuneta; Yukio Katsukawa; Masumi Shimojo; Toshifumi Shimizu; Richard A. Shine; Theodore D. Tarbell; Alan M. Title; Bruce Lites; Masahito Kubo; Shin'ichi Nagata; Takaaki Yokoyama

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Nov. 2007

  
• Triggering mechanism for the filament eruption on 2005 September 13 in NOAA active region 10808

  Kaori Nagashima; Hiroaki Isobe; Takaaki Yokoyama; Takako T. Ishii; Takenori J. Okamoto; Kazunari Shibata

  ASTROPHYSICAL JOURNAL, Oct. 2007

  
• Imaging spectroscopy of a gradual hardening flare on 2000 November 25

  Hiroyuki Takasaki; Junko Kiyohara; Ayumi Asai; Hiroshi Nakajima; Takaaki Yokoyama; Satoshi Masuda; Jun Sato; Takeo Kosugi

  ASTROPHYSICAL JOURNAL, Jun. 2007

  
• The origin of ripples in cool cores of galaxy clusters: Heating by magnetohydrodynamic waves?

  Yutaka Fujita; Takeru K. Suzuki; Takahiro Kudoh; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Apr. 2007

  
• Evolution of H alpha kernels and energy release in an X-class flare

  Ayumi Asai; Takaaki Yokoyama; Masumi Shimojo; Satoshi Masuda; Kazunari Shibata

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Three-dimensional MHD Simulations of emerging flux and associated magnetic reconnection

  Hiroaki Isobe; Takehiro Miyagoshi; Kazunari Shibata; Takaaki Yokoyama

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Quantitative analysis of nonthermal electrons in impulsive hard X-ray flares

  Takashi Minoshima; Takaaki Yokoyama

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Magnetohydrodynamic numerical simulations of emerging flux tube for studying effects of twist intensity

  Takehiro Miyagoshi; Hiroaki Isobe; Takaaki Yokoyama; Kazunari Shibata

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Three-dimensional filament eruption driven by an emerging flux

  Shun Notoya; Takaaki Yokoyama; Kanya Kusano; Takashi Sakurai; Takehiro Miyagoshi; Hiroaki Isobe; Tetsuya Yamamoto

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Helicity injection in regions of various magnetic fluxes

  Tetsuya T. Yamamoto; Takashi Sakurai; Kanya Kusano; Takaaki Yokoyama

  NEW SOLAR PHYSICS WITH SOLAR-B MISSION, 2007

  
• Statistical study of the reconnection rate in solar flares observed with Yohkoh SXT

  Kaori Nagashima; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Aug. 2006

  
• Two-dimensional magnetohydrodynamic simulations of relativistic magnetic reconnection

  Naoyuki Watanabe; Takaaki Yokoyama

  ASTROPHYSICAL JOURNAL, Aug. 2006

  
• Flare ribbon expansion and energy release

  Ayumi Asai; Takaaki Yokoyama; Masumi Shimojo

  JOURNAL OF ASTROPHYSICS AND ASTRONOMY, Jun. 2006

  
• Three-dimensional simulation of solar emerging flux using the earth simulator I. Magnetic Rayleigh-Taylor instability at the top of the emerging flux as the origin of filamentary structure

  Hiroaki Isobe; Takehiro Miyagoshi; Kazunari Shibata; Takaaki Yokoyama

  PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, Apr. 2006

  
• Magnetohydrodynamic numerical simulations of emerging flux and associated active phenomena in the solar atmosphere

  Takehiro Miyagoshi; Hiroaki Isobe; Takaaki Yokoyama; Kazunari Shibata

  NUMERICAL MODELING OF SPACE PLASMA FLOWS: ASTRONUM-2006, 2006

  
• Reconnection rate in the decay phase of a long duration event flare on 1997 May 12

  Hiroaki Isobe; Takaaki Yokoyama; Masumi Shimojo; Taro Morimoto; Hiromichi Kozu; E. T.O. Shigeru; Noriyuki Narukage; Kazunari Shibata

  Astrophysical Journal, 10 Feb. 2002

  

Misc.

• Relation between magnetic helicity injection and flare activities in active region NOAA 8100

  T Yokoyama; K Kusano; T Maeshiro; T Sakurai

  MAGNETIC HELICITY AT THE SUN, IN SOLAR WIND AND MAGNETOSPHERES: VISTAS FROM X-RAY OBSERVATORIES, 2003

  
• Measurement of magnetic helicity flux into the solar corona

  K Kusano; T Maeshiro; T Yokoyama; T Sakurai

  MAGNETIC HELICITY AT THE SUN, IN SOLAR WIND AND MAGNETOSPHERES: VISTAS FROM X-RAY OBSERVATORIES, 2003

  
• Two-Dimensional MHD Numerical Simulations of Magnetic Reconnection Triggered by A Supernova Shock in Interstellar Medium, Generation of X-Ray Gas in Galaxy

  Syuniti Tanuma; Takaaki Yokoyama; Takahiro Kudoh; Kazunari Shibata

  ApJ, 06 Sep. 2000

  
• Coronal X-Ray Jets Observed with the Yohkoh Soft X-Ray Telescope

  SHIBATA Kazunari; YOKOYAMA Takaaki; SHIMOJO Masumi

  Journal of geomagnetism and geoelectricity, Jan. 1996

  
• 25pXA-6 Rayleigh-Taylor instability and patchy magnetic reconnection in solar emerging flux region

  Isobe Hiroaki; Miyagoshi Takehiro; Shibata Kazunari; Yokoyama Takaaki

  Meeting abstracts of the Physical Society of Japan, 04 Mar. 2005

  
• 25pXA-5 Emerging process of a twisted magnetic flux tube from the photosphere to the corona

  Miyagoshi Takehiro; Isobe Hiroaki; Yokoyama Takaaki; Shibata Kazunari

  Meeting abstracts of the Physical Society of Japan, 04 Mar. 2005

  
• Hydrodynamic Modeling of a Flare Loop Connecting the Accretion Disk and Central Core of Young Stellar Objects

  ISOBE Hiroaki; SHIBATA Kazunari; YOKOYAMA Takaaki; IMANISHI Kensuke

  Publications of the Astronomical Society of Japan, 25 Oct. 2003

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• Three-Dimensional Magnetohydrodynamic Numerical Simulations of Coronal Loop Oscillations Associated with Flares

  MIYAGOSHI Takehiro; YOKOYAMA Takaaki; SHIMOJO Masumi

  Publications of the Astronomical Society of Japan, 25 Feb. 2004

  
• The Two-step Emergence of the Magnetic Flux Tube at the Solar Convection Zone and the Photosphere

  Toriumi Shin; Yokoyama Takaaki

  日本流体力学会年会講演論文集, 2009

  
• MHD Simulations of a Current Sheet with a Finite Resistivity Perturvations

  Yokoyama T.; Isobe H.

  日本流体力学会年会講演論文集, 2008

  
• AM06-19-002 MHD simulation of solar emerging flux region using the Earth Simulator

  Isobe Hiroaki; Miyagoshi Takehiro; Shibata Kazunari; Yokoyama Takaaki

  日本流体力学会年会講演論文集, 2006

  
• AM05-08-008 Three-dimensional magnetic reconnection driven by an emerging flux tube with coronal arcade field in the Sun

  Notoya Shun; Yokoyama Takaaki; Kusano Kanya; Sakurai Takashi; Miyagoshi Takahiro; Isobe Hiroaki; Yamamoto Tetsuya

  日本流体力学会年会講演論文集, 2005

  
• D335 MHD Numerical Simulations of Solar Coronal Jets

  MIYAGOSHI Takehiro; YOKOYAMA Takaaki; ISOBE Hiroaki; SHIBATA Kazunari

  日本流体力学会年会講演論文集, 2004

  
• MHD Simulations of a Current Sheet with a Finite Resistivity Perturvations : Guide-field effect

  Yokoyama T.; Isobe H.

  日本流体力学会年会講演論文集, 2010

  
• Two-dimensional Magnetohydrodynamic Simulations on the Solar Flux Emergence

  Toriumi Shin; Yokoyama Takaaki

  日本流体力学会年会講演論文集, 2010

  
• 30pSA-3 MHD Simulations of a current sheet with initial perturbation on resistivity

  Yokoyama T.; Isobe H.

  Meeting abstracts of the Physical Society of Japan, 03 Mar. 2009

  

External funds: Kakenhi

• Understanding and realization of advanced prediction for solar explosions with the integrated model including from stellar convection zone to interplanetary space

  Grant-in-Aid for Scientific Research (A)

  Medium-sized Section 16:Astronomy and related fields

  Nagoya University

  草野 完也

  From 05 Apr. 2021, To 31 Mar. 2026, Granted

  太陽;ダイナモ;フレア;CME;シミュレーション;太陽対流層;宇宙天気;予測

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21H04492/
• Theoretical studies on evolution of stellar coronae

  Grant-in-Aid for Scientific Research (B)

  Basic Section 16010:Astronomy-related

  Kyoto University

  Takaaki Yokoyama

  From 01 Apr. 2021, To 31 Mar. 2024, Project Closed

  太陽;恒星;プラズマ;磁気流体;コロナ;ダイナモ

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21H01124/
• New Physical Picture of Plasma Heating Revealed by Advanced Large Solar Telescope DKIST

  Fund for the Promotion of Joint International Research (Fostering Joint International Research (B))

  Medium-sized Section 16:Astronomy and related fields

  Japan Aerospace EXploration Agency

  鳥海 森

  From 27 Oct. 2020, To 31 Mar. 2025, Granted

  超大型太陽望遠鏡DKIST;太陽観測衛星ひので;光球・彩層磁場;輻射磁気流体シミュレーション;偏光分光観測

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20KK0072/
• Formation of X-ray Emitting Regions and the Origin of Time Variabilities in Accretion Flow onto a Supermassive Black Hole

  Grant-in-Aid for Scientific Research (B)

  Chiba University

  Ryoji MATSUMOTO

  From 01 Apr. 2016, To 31 Mar. 2019, Project Closed

  理論天文学;活動銀河中心核;X線天文学;ブラックホール;磁気流体シミュレーション;宇宙ジェット;状態遷移;輻射スペクトル;Ｘ線天文学;磁気リコネクション

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16H03954/
• Theoretical study on the dynamics and heating in the solar chromosphere

  Grant-in-Aid for Scientific Research (B)

  The University of Tokyo

  Takaaki Yokoyama

  From 01 Apr. 2015, To 31 Mar. 2020, Project Closed

  天文;太陽物理学;プラズマ

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15H03640/
• Dynamo mechanism in galaxies: nonlinear dynamics driven by cosmic rays and magnetic fields

  Grant-in-Aid for Scientific Research (C)

  National Astronomical Observatory of Japan

  Takahiro KUDOH

  From 28 Apr. 2011, To 31 Mar. 2015, Project Closed

  天文;宇宙物理;理論天文学;流体力学;流体

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23540274/
• Research of generation mechanisms and dynamics of solar magnetic fields

  Grant-in-Aid for Scientific Research (B)

  The University of Tokyo

  Takaaki YOKOYAMA

  From 01 Apr. 2011, To 31 Mar. 2015, Project Closed

  天文;太陽物理学;プラズマ

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23340042/
• Studies of State Transitions in Black Hole Candidates by Collaboration between Magnetohydrodynamic Simulations and X-ray Observations

  Grant-in-Aid for Scientific Research (B)

  Chiba University

  Ryoji MATSUMOTO

  From 01 Apr. 2011, To 31 Mar. 2014, Project Closed

  理論天文学;X線天文学;降着円盤;磁気流体力学;シミュレーション;ブラックホール;宇宙ジェット;天体プラズマ;Ｘ線天文学;潮汐破壊;幅射流体力学;数値天体物理学

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23340040/
• Developments of Numerical Magnetohydrodynamic Simulators of Accretion Disks with Application to Time Variabilities and Jet Formation

  Grant-in-Aid for Scientific Research (B)

  Chiba University

  Ryoji MATSUMOTO

  From 01 Apr. 2008, To 31 Mar. 2011, Project Closed

  理論天文学;数値天体物理学;磁気流体力学;降着円盤;宇宙ジェット;ブラックホール;輻射流体力学;X線天文学

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20340040/
• Studies of Explosive Processes of the Hot Plasmas in the Sun and Astronomical Object

  Grant-in-Aid for Scientific Research (C)

  The University of Tokyo

  Takaaki YOKOYAMA

  From 01 Apr. 2006, To 31 Mar. 2010, Project Closed

  太陽物理学;天文;プラズマ・核融合;太陽;天体プラズマ;コロナ;磁気リコネクション;X線

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18540230/
• 電磁流体力学による太陽活動の統合シミュレーション

  Grant-in-Aid for Scientific Research (B)

  Kyoto University

  柴田 一成

  From 01 Apr. 2004, To 31 Mar. 2007, Project Closed

  フレア;コロナ質量放出;磁気リコネクション;シミュレーション;電磁流体力学;ジェット;コロナ加熱;宇宙天気

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16340058/
• Research on the Formation and Activity of Galactic Nuclear Gas Disks Including Magnetohydrodynamical Processes

  Grant-in-Aid for Scientific Research (B)

  Chiba University

  Ryoji MATSUMOTO

  From 01 Apr. 2004, To 31 Mar. 2006, Project Closed

  銀河円盤;降着円盤;磁気流体力学;数値実験;活動銀河中心核;宇宙ジェット;自己重力;銀河ダイナモ, Galactic Disk;Accretion Disk;Magnetohydrodynamics;Numerical Simulation;Active Galactic Nuclei;Astrophysical Jets;Self Gravity;Galactic Dynamo

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16340052/
• 天体高温プラズマ活動現象の、磁気エネルギー蓄積過程と解放過程との研究

  Grant-in-Aid for Young Scientists (B)

  The University of Tokyo

  横山 央明

  From 01 Apr. 2003, To 31 Mar. 2006, Project Closed

  太陽;天体プラズマ;コロナ;磁気リコネクション;X線;天体高温プラズマ

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15740125/
• 新展開を迎えた磁気リコネクション研究に関する企画調査-実験室から天体まで-

  Grant-in-Aid for Scientific Research (C)

  Kyoto University

  柴田 一成

  From 01 Apr. 2003, To 31 Mar. 2004, Project Closed

  フレア;ガンマ線バースト;磁気リコネクション;ジェット;プラズモイド;電磁流体力学;シミュレーション

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15634016/
• STUDY OF SOLAR FLARE MECHANISM AND ITS APPLICATION TO GAMMA RAY BURSTS

  Grant-in-Aid for Scientific Research (C)

  KYOTO UNIVERSITY

  Kazunari SHIBATA

  From 01 Apr. 2002, To 31 Mar. 2004, Project Closed

  フレア;ガンマ線バースト;磁気リコネクション;ジェット;プラズモイド;電磁流体力学;シミュレーション, flare;gamma ray bursts;magnetic reconnection;jet;plasmoid;magnetohydrodynamics;simulation

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540226/
• Basic studies of cosmic ray shock acceleration processes

  Grant-in-Aid for Scientific Research (B)

  The University of Tokyo

  Toshio TERASAWA

  From 01 Apr. 2002, To 31 Mar. 2005, Project Closed

  衝撃波;粒子加速;太陽フレア;超強磁場中性子星;磁気圏;プラズマシート;相対論的ジェット;ブレーザー;衝撃波粒子加速;太陽コロナ加熱;磁気リコネクション;磁気ヘリシティ;地球前面定在衝撃波;サイクロトロン共鳴;スローショック;ガンマ線バースト;衝撃波交差;ピックアップイオン, shocks;particle acceleration;solar flares;magnetar;magnetosphere;plasma sheet;relativistic jets;blazars

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14340066/
• 天体高温ガス加熱の磁気流体数値シミュレーション

  Grant-in-Aid for Encouragement of Young Scientists (A)

  National Astronomical Observatory of Japan

  横山 央明

  From 01 Apr. 2000, To 31 Mar. 2002, Project Closed

  プラズマ;磁気流体力学;数値シミュレーション;太陽;コロナ;磁気流体力

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12740127/
• Study of Activity Mechanism in the Solar Corona Based on Realistic-Data Simulations

  Grant-in-Aid for Scientific Research (C)

  HIROSHIMA UNIVERSIlY

  Kannya KUSANO

  From 01 Apr. 2000, To 31 Mar. 2004, Project Closed

  太陽;フレア;コロナ;MHD;シミュレーション;リコネクション;磁気ヘリシティ;プラズマ;ヘリシティ;太陽磁場;不安定性, the Sun;flares;corona;MHD;simulation;reconnection;magnetic helicity;plasma

  https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640236/

Education

Teaching subject(s)

• From 01 Apr. 2024, To 31 Mar. 2025

  Introduction to Plasma Science

  N222, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2024, To 31 Mar. 2025

  Introduction to General Astronomy

  N516, Spring, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2024, To 31 Mar. 2025

  Introduction to General Astronomy

  N516, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2024, To 31 Mar. 2025

  Fundamental Physics B

  N226, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2024, To 31 Mar. 2025

  Seminar on Solar and Cosmic Plasmas A

  4014, Spring, Graduate School of Science, 1
• From 01 Apr. 2024, To 31 Mar. 2025

  Seminar on Solar and Cosmic Plasmas D

  4017, Fall, Graduate School of Science, 1
• From 01 Apr. 2024, To 31 Mar. 2025

  Seminar on Solar and Cosmic Plasmas C

  4016, Spring, Graduate School of Science, 1
• From 01 Apr. 2024, To 31 Mar. 2025

  Seminar on Solar and Cosmic Plasmas B

  4015, Fall, Graduate School of Science, 1
• From 01 Apr. 2024, To 31 Mar. 2025

  Special study course II(Physical Science) S2

  5251, Year-long, Faculty of Science, 12
• From 01 Apr. 2024, To 31 Mar. 2025

  Fundamental Astrophysics II (Astronomical hydro and magnetohydrodynamics)

  3314, Spring, Faculty of Science, 2
• From 01 Apr. 2024, To 31 Mar. 2025

  Physics of Solar and Cosmic Plasmas

  4048, Spring, Graduate School of Science, 2
• From 01 Apr. 2023, To 31 Mar. 2024

  Introduction to General Astronomy

  N516, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2023, To 31 Mar. 2024

  Fundamental Physics B

  N226, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2023, To 31 Mar. 2024

  Introduction to Plasma Science

  N222, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2023, To 31 Mar. 2024

  Introduction to General Astronomy

  N516, Spring, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2023, To 31 Mar. 2024

  Seminar on Solar and Cosmic Plasmas A

  4014, Spring, Graduate School of Science, 1
• From 01 Apr. 2023, To 31 Mar. 2024

  Seminar on Solar and Cosmic Plasmas D

  4017, Fall, Graduate School of Science, 1
• From 01 Apr. 2023, To 31 Mar. 2024

  Seminar on Solar and Cosmic Plasmas C

  4016, Spring, Graduate School of Science, 1
• From 01 Apr. 2023, To 31 Mar. 2024

  Seminar on Solar and Cosmic Plasmas B

  4015, Fall, Graduate School of Science, 1
• From 01 Apr. 2023, To 31 Mar. 2024

  Special study course II(Physical Science) S2

  5251, Year-long, Faculty of Science, 12
• From 01 Apr. 2023, To 31 Mar. 2024

  Fundamental Astrophysics II (Astronomical hydro and magnetohydrodynamics)

  3314, Spring, Faculty of Science, 2
• From 01 Apr. 2022, To 31 Mar. 2023

  Fundamental Astrophysics II (Astronomical hydro and magnetohydrodynamics)

  3314, Spring, Faculty of Science, 2
• From 01 Apr. 2022, To 31 Mar. 2023

  Physics of Solar and Cosmic Plasmas

  4048, Spring, Graduate School of Science, 2
• From 01 Apr. 2022, To 31 Mar. 2023

  Seminar on Solar and Cosmic Plasmas D

  4017, Fall, Graduate School of Science, 1
• From 01 Apr. 2022, To 31 Mar. 2023

  Seminar on Solar and Cosmic Plasmas C

  4016, Spring, Graduate School of Science, 1
• From 01 Apr. 2022, To 31 Mar. 2023

  Seminar on Solar and Cosmic Plasmas A

  4014, Spring, Graduate School of Science, 1
• From 01 Apr. 2022, To 31 Mar. 2023

  Seminar on Solar and Cosmic Plasmas B

  4015, Fall, Graduate School of Science, 1
• From 01 Apr. 2022, To 31 Mar. 2023

  Introduction to General Astronomy

  N516, Spring, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2022, To 31 Mar. 2023

  Fundamental Physics B

  N226, Fall, Institute for Liberal Arts and Sciences, 2
• From 01 Apr. 2022, To 31 Mar. 2023

  Special study course II(Physical Science) S2

  5251, Year-long, Faculty of Science, 12
• From 01 Apr. 2022, To 31 Mar. 2023

  Introduction to General Astronomy

  N516, Fall, Institute for Liberal Arts and Sciences, 2

Participation in PhD Defense

• A research on the long-term evolution of various types of supernova remnants and a proposal of novel environment of Tycho’s supernova remnant

  KOBASHI RYOSUKE, Graduate School of Science, Sub-chief Examiner

  25 Mar. 2024
• Theoretical and Observational Studies of Small-Scale Flares and Associated Mass Ejections / Jets

  KOTANI YUJI, Graduate School of Science, Sub-chief Examiner

  23 Mar. 2023
• Observational and Numerical Studies of Solar Coronal Magnetic Field

  YAMASAKI DAIKI, Graduate School of Science, Sub-chief Examiner

  23 Mar. 2023
• Observational Study of Gradual Solar Energetic Particle Events Focusing on Timescale

  KIHARA KOSUKE, Graduate School of Science, Sub-chief Examiner

  23 Mar. 2023

Administration

School management (title, position)

• From 01 Apr. 2022, To 31 Mar. 2024

  天文台 台長

Faculty management (title, position)

• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科危機管理委員会委員
• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科専攻長会議構成員
• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科技術部協議会委員
• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科将来計画委員会委員
• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科予算委員会委員
• From 01 Apr. 2024, To 31 Mar. 2025

  理学研究科自己点検・評価委員会委員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科将来計画委員会委員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科自己点検・評価委員会委員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科情報セキュリティ委員会委員
• From 01 Apr. 2023, To 31 Mar. 2025

  理学研究科天文台運営協議会委員
• From 01 Apr. 2023, To 31 Mar. 2025

  地磁気世界資料解析センター運営協議会委員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科研究科会議構成員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科専攻長会議構成員
• From 01 Apr. 2023, To 31 Mar. 2024

  理学研究科危機管理委員会委員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科将来計画委員会委員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科自己点検・評価委員会委員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科SACRA広報・社会連携部門委員会　基金運営小委員会委員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科情報セキュリティ委員会委員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科研究科会議構成員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科専攻長会議構成員
• From 01 Apr. 2022, To 31 Mar. 2023

  理学研究科危機管理委員会委員
• From 01 May 2021, To 31 Mar. 2023

  理学研究科天文台運営協議会議員