igata takahisa 伊形尚久

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IGATA Takahisa 伊形尚久

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Researcher Number	40711487
Other IDs	https://orcid.org/0000-0002-3344-9045
Affiliation (Current)	2025: 学習院大学, 理学部, 助教
Affiliation (based on the past Project Information) *help	2022 – 2024: 学習院大学, 理学部, 助教 2020 – 2021: 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 博士研究員 2019: 立教大学, 理学部, 特定課題研究員
Review Section/Research Field	Principal Investigator Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics Except Principal Investigator Medium-sized Section 11:Algebra, geometry, and related fields
Keywords	Principal Investigator 一般相対論 / ブラックホール / 宇宙物理 / 重力 / 相対論 / 近点シフト / ダークマター / 光子リング / 脱出確率 / 対称性 … More / シャドウ / 臨界極限 / ニアホライズン対称性 / 光子脱出確率 / ブラックホールシャドウ … More Except Principal Investigator ADM理論 / 測地流の可積分性 / ペンローズ不等式 / 部分多様体の曲率流 / 幾何学的曲率流 / 微分幾何学 / アインシュタイン方程式 / 高次元重力ソリトン / 調和写像 / 重力波天文学 / 一般相対性理論 Less

Geometric studies of the Einstein equation via theoretical physics and gravitational astronomy
- Principal Investigator
  
  山田澄生
- Project Period (FY)
  2024 – 2028
- Research Category
  
  Grant-in-Aid for Scientific Research (A)
- Review Section
  
  Medium-sized Section 11:Algebra, geometry, and related fields
- Research Institution
  Gakushuin University
Geometry of Gravitational Fields
- Principal Investigator
  
  山田澄生
- Project Period (FY)
  2023 – 2026
- Research Category
  
  Fund for the Promotion of Joint International Research (International Collaborative Research)
- Review Section
  
  Medium-sized Section 11:Algebra, geometry, and related fields
- Research Institution
  Gakushuin University
ブラックホールの同定に向けた理論的枠組みの構築Principal Investigator
- Principal Investigator
  
  伊形尚久
- Project Period (FY)
  2022 – 2025
- Research Category
  
  Grant-in-Aid for Scientific Research (C)
- Review Section
  
  Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
- Research Institution
  Gakushuin University
Symmetry and shadow of the near-extremal Kerr black holePrincipal Investigator
- Principal Investigator
  
  IGATA Takahisa
- Project Period (FY)
  2019 – 2022
- Research Category
  
  Grant-in-Aid for Early-Career Scientists
- Review Section
  
  Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
- Research Institution
  Gakushuin University
  High Energy Accelerator Research Organization
  Rikkyo University

All 2023 2022 2021 2020 2019 Other

All Journal Article Presentation Other

[Journal Article] Periapsis shifts in dark matter distribution around a black hole2023
- Author(s)
  Takahisa Igata, Tomohiro Harada, Hiromi Saida, Yohsuke Takamori
- Journal Title
  
  International Journal of Modern Physics D
  
  Volume: 32 Issue: 16 Pages: 2350105-2350105
- DOI
  10.1142/s0218271823501055
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-22K03611, KAKENHI-PROJECT-19K03876, KAKENHI-PLANNED-20H05853
[Journal Article] General formulae for the periapsis shift of a quasi-circular orbit in static spherically symmetric spacetimes and the active gravitational mass density2023
- Author(s)
  Tomohiro Harada, Takahisa Igata, Hiromi Saida, Yohsuke Takamori
- Journal Title
  
  International Journal of Modern Physics D
  
  Volume: 32 Issue: 15 Pages: 2350098-2350098
- DOI
  10.1142/s0218271823500980
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-22K03611, KAKENHI-PROJECT-19K03876, KAKENHI-PLANNED-20H05853
[Journal Article] Periapsis shifts in dark matter distribution with a dense core2022
- Author(s)
  Takahisa Igata, Yohsuke Takamori
- Journal Title
  
  Physical Review D
  
  Volume: 105 Issue: 12 Pages: 124029-124029
- DOI
  10.1103/physrevd.105.124029
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-22K03611, KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-19H01900
[Journal Article] Photon escape in the extremal Kerr black hole spacetime2022
- Author(s)
  Kota Ogasawara, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 105 Issue: 2 Pages: 024031-024031
- DOI
  10.1103/physrevd.105.024031
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-20K14467, KAKENHI-PROJECT-20J00416
[Journal Article] Photon emission from inside the innermost stable circular orbit2021
- Author(s)
  Takahisa Igata, Kazunori Kohri, Kota Ogasawara
- Journal Title
  
  Physical Review D
  
  Volume: 103 Issue: 10 Pages: 104028-104028
- DOI
  10.1103/physrevd.103.104028
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-20K14467, KAKENHI-PROJECT-20J00416
[Journal Article] Stable circular orbits in caged black hole spacetimes2021
- Author(s)
  Takahisa Igata, Shinya Tomizawa
- Journal Title
  
  Physical Review D
  
  Volume: 103 Issue: 8 Pages: 084011-084011
- DOI
  10.1103/physrevd.103.084011
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-17K05452, KAKENHI-PROJECT-19K14715
[Journal Article] Photon surfaces in less symmetric spacetimes2021
- Author(s)
  Yasutaka Koga, Takahisa Igata, Keisuke Nakashi
- Journal Title
  
  Physical Review D
  
  Volume: 103 Issue: 4 Pages: 044003-044003
- DOI
  10.1103/physrevd.103.044003
- Peer Reviewed / Open Access
- Data Source
  KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-19J12007
[Journal Article] Stable circular orbits in Kaluza-Klein black hole spacetimes2021
- Author(s)
  Shinya Tomizawa, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 103 Issue: 12 Pages: 124004-124004
- DOI
  10.1103/physrevd.103.124004
- Peer Reviewed / Open Access
- Data Source
  KAKENHI-PROJECT-19K14715
[Journal Article] Complete classification of photon escape in the Kerr black hole spacetime2021
- Author(s)
  Kota Ogasawara, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 103 Issue: 4 Pages: 044029-044029
- DOI
  10.1103/physrevd.103.044029
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-20K14467, KAKENHI-PROJECT-20J00416
[Journal Article] Chaos in a generalized Euler’s three-body problem2021
- Author(s)
  Takahisa Igata
- Journal Title
  
  Classical and Quantum Gravity
  
  Volume: 38 Issue: 19 Pages: 195009-195009
- DOI
  10.1088/1361-6382/ac1be7
- Data Source
  KAKENHI-PROJECT-19K14715
[Journal Article] Escape probability of a photon emitted near the black hole horizon2020
- Author(s)
  Kota Ogasawara, Takahisa Igata, Tomohiro Harada, Umpei Miyamoto
- Journal Title
  
  Physical Review D
  
  Volume: 101 Issue: 4 Pages: 1-11
- DOI
  10.1103/physrevd.101.044023
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-18K03652, KAKENHI-PROJECT-19K03876, KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-18J10275
[Journal Article] Particle dynamics in the Newtonian potential sourced by a homogeneous circular ring2020
- Author(s)
  Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 101 Issue: 12 Pages: 124064-124064
- DOI
  10.1103/physrevd.101.124064
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715
[Journal Article] Observability of the innermost stable circular orbit in a near-extremal Kerr black hole2020
- Author(s)
  Takahisa Igata, Keisuke Nakashi, Kota Ogasawara
- Journal Title
  
  Physical Review D
  
  Volume: 101 Issue: 4 Pages: 044044-044044
- DOI
  10.1103/physrevd.101.044044
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715, KAKENHI-PROJECT-18J10275
[Journal Article] Chaotic particle motion around a homogeneous circular ring2020
- Author(s)
  Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 102 Issue: 4 Pages: 044019-044019
- DOI
  10.1103/physrevd.102.044019
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715
[Journal Article] Stable bound orbits in black lens backgrounds2020
- Author(s)
  Shinya Tomizawa,Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 102 Issue: 12 Pages: 124079-124079
- DOI
  10.1103/physrevd.102.124079
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-17K05452, KAKENHI-PROJECT-19K14715
[Journal Article] Stable circular orbits in higher-dimensional multi-black hole spacetimes2020
- Author(s)
  Takahisa Igata, Shinya Tomizawa
- Journal Title
  
  Physical Review D
  
  Volume: 8 Issue: 8 Pages: 084003-084003
- DOI
  10.1103/physrevd.102.084003
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-17K05452, KAKENHI-PROJECT-19K14715
[Journal Article] Massive tensor field perturbations on extremal and near-extremal static black holes2019
- Author(s)
  Vitor Cardoso, Takahisa Igata, Akihiro Ishibashi, Kodai Ueda
- Journal Title
  
  Physical Review D
  
  Volume: 100 Issue: 4 Pages: 044013-044013
- DOI
  10.1103/physrevd.100.044013
- NAID
  130008148523
- Peer Reviewed / Int'l Joint Research
- Data Source
  KAKENHI-PROJECT-15K05092, KAKENHI-PROJECT-19K14715
[Journal Article] Innermost stable circular orbits in the Majumdar-Papapetrou dihole spacetime2019
- Author(s)
  Keisuke Nakashi, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 99 Issue: 12 Pages: 124033-124033
- DOI
  10.1103/physrevd.99.124033
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715
[Journal Article] Stable bound orbits around a supersymmetric black lens2019
- Author(s)
  Shinya Tomizawa, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 100 Issue: 12 Pages: 124031-124031
- DOI
  10.1103/physrevd.100.124031
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-17K05452, KAKENHI-PROJECT-19K14715
[Journal Article] Effect of a second compact object on stable circular orbits2019
- Author(s)
  Keisuke Nakashi, Takahisa Igata
- Journal Title
  
  Physical Review D
  
  Volume: 100 Issue: 10 Pages: 104006-104006
- DOI
  10.1103/physrevd.100.104006
- Peer Reviewed
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 一般的な静的球対称時空における準円軌道の近点移動2023
- Author(s)
  原田知広, 伊形尚久, 斉田浩見, 孝森洋介
- Organizer
  日本天文学会2023年春季年会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Near-Horizon Extremal-Kerr geometryを用いた光の脱出確率の解析的導出2023
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会 2023年春季大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] Rotating fluid with anisotropic pressure in (2 + 1) dimensions2023
- Author(s)
  伊形尚久, 孝森洋介
- Organizer
  日本物理学会第78回年次大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] 一般的な静的球対称時空における準円軌道の近点移動2023
- Author(s)
  原田知広, 伊形尚久, 斉田浩見, 孝森洋介
- Organizer
  日本天文学会2023年春季年会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] Near-Horizon Extremal-Kerr geometryを用いた光の脱出確率の解析的導出2023
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会 2023年春季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 静的球対称時空における準円軌道の近点移動の一般公式と能動的重力質量密度2023
- Author(s)
  原田知広, 伊形尚久, 斉田浩見, 孝森洋介
- Organizer
  日本物理学会第78回年次大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] 動径圧力をもたない相対論的静的球解の構成とテスト粒子の円軌道の解析2022
- Author(s)
  孝森洋介, 伊形尚久
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] ブラックホール周辺のダークマター分布における近点移動2022
- Author(s)
  伊形尚久, 原田知広, 斉田浩見, 孝森洋介
- Organizer
  日本天文学会2022年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] FLRW解の共形境界の分類：線形状態方程式の場合 II2022
- Author(s)
  原田知広, 伊形尚久A, 佐藤琢磨, Bernard Carr
- Organizer
  日本物理学会第77回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Photon emission in the near-horizon extremal Kerr geometry2022
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] 球対称時空における近点移動のSchwarzschildからのずれ2022
- Author(s)
  原田知広, 伊形尚久, 斉田浩見, 孝森洋介
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] 球対称時空における近点移動のSchwarzschildからのずれ2022
- Author(s)
  原田知広, 伊形尚久, 斉田浩見, 孝森洋介
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] ブラックホール周辺のダークマター分布における近点移動2022
- Author(s)
  伊形尚久, 原田知広, 斉田浩見, 孝森洋介
- Organizer
  日本天文学会2022年秋季大会
- Data Source
  KAKENHI-PROJECT-22K03611
[Presentation] Periapsis/apoapsis shift in static clouds around a black hole2022
- Author(s)
  伊形尚久, 原田知広, 斉田浩見, 孝森洋介
- Organizer
  日本物理学会第77回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 動径圧力をもたない相対論的静的球解の構成とテスト粒子の円軌道の解析2022
- Author(s)
  孝森洋介, 伊形尚久
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Photon emission in the near-horizon extremal Kerr geometry2022
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会 2022年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Retrograde periapsis shift due to extended matter distributions2021
- Author(s)
  伊形尚久, 孝森洋介
- Organizer
  日本物理学会 2021年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] FLRW解の共形境界の分類：線形状態方程式の場合2021
- Author(s)
  原田知広, 伊形尚久, 佐藤琢磨
- Organizer
  日本物理学会 2021年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Photon surfaces in less symmetric spacetimes2021
- Author(s)
  古賀泰敬, 伊形尚久, 中司桂輔
- Organizer
  日本物理学会第76回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Kerr-Newman時空における光の脱出と分類2021
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会 2021年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] ブラックレンズの安定束縛軌道について2021
- Author(s)
  富沢真也, 伊形尚久
- Organizer
  日本物理学会第76回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Photon emission from inside the innermost stable circular orbit2021
- Author(s)
  伊形尚久, 郡和範, 小笠原康太
- Organizer
  日本物理学会第76回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Complete classification of photon escape in the Kerr black hole spacetime2021
- Author(s)
  小笠原康太, 伊形尚久
- Organizer
  日本物理学会第76回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Retrograde periapsis shift due to extended matter distribution2021
- Author(s)
  Takahisa Igata
- Organizer
  The 30th Workshop on General Relativity and Gravitation in Japan
- Int'l Joint Research
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 近臨界Kerrブラックホールの最内安定円軌道の観測可能性2020
- Author(s)
  伊形尚久、中司桂輔、小笠原康太
- Organizer
  日本物理学会2020年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] ブラックレンズ時空の測地線2020
- Author(s)
  富沢真也, 伊形尚久
- Organizer
  日本物理学会第75回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 第2のコンパクト天体が与える安定周回軌道への影響2020
- Author(s)
  中司桂輔, 伊形尚久
- Organizer
  日本物理学会第75回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Observability of the innermost stable circular orbit in a near-extremal Kerr black hole2020
- Author(s)
  Takahisa Igata
- Organizer
  online JGRG 2020
- Int'l Joint Research
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] ブラックホールシャドウの外縁部上の偏光パターンと重力ファラデー回転2020
- Author(s)
  伊形尚久, 石原秀樹, 高橋真聡
- Organizer
  日本物理学会第75回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 非球対称時空におけるphoton surface2020
- Author(s)
  古賀泰敬, 伊形尚久, 中司桂輔
- Organizer
  日本物理学会2020年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] 地平面近傍からの光の脱出確率2020
- Author(s)
  小笠原康太, 伊形尚久, 原田知広, 宮本雲平
- Organizer
  日本物理学会第75回年次大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] ブラックレンズ周りの光の安定束縛軌道2019
- Author(s)
  富沢真也, 伊形尚久
- Organizer
  日本物理学会2019年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Polarization propagation to a photon ring2019
- Author(s)
  伊形尚久, 石原秀樹, 高橋真聡
- Organizer
  BZ77研究会2019
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Polarization distribution on the edge of a black hole shadow2019
- Author(s)
  Takahisa Igata, Hideki Ishihara, Masaaki Takahashi
- Organizer
  The 29th Workshop on General Relativity and Gravitation in Japan
- Int'l Joint Research
- Data Source
  KAKENHI-PROJECT-19K14715
[Presentation] Can we observe spherical photon orbits in near-extremal Kerr black holes?2019
- Author(s)
  伊形尚久, 石原秀樹, 安西悠
- Organizer
  日本物理学会2019年秋季大会
- Data Source
  KAKENHI-PROJECT-19K14715
[]

1. 山田澄生 (90396416)

# of Collaborated Projects: 2 results

# of Collaborated Products: 0 results
2. 白水徹也 (10282716)

# of Collaborated Projects: 2 results

# of Collaborated Products: 0 results
3. 服部広大 (30586087)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
4. 儀我美一 (70144110)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
5. 小野寺有紹 (70614999)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
6. 安東正樹 (90313197)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
7. 高津飛鳥 (90623554)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
8. 古賀泰敬 (60910891)

# of Collaborated Projects: 1 results

# of Collaborated Products: 0 results
9. ISHIBASHI Akihiro

# of Collaborated Projects: 0 results

# of Collaborated Products: 1 results
10. MIYAMOTO Umpei

# of Collaborated Projects: 0 results

# of Collaborated Products: 1 results
11. TOMIZAWA Shin'ya

# of Collaborated Projects: 0 results

# of Collaborated Products: 4 results

igata takahisa 伊形 尚久

IGATA Takahisa 伊形 尚久

Research Projects

Research Products

Co-Researchers

Geometric studies of the Einstein equation via theoretical physics and gravitational astronomy

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Geometry of Gravitational Fields

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ブラックホールの同定に向けた理論的枠組みの構築Principal Investigator

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Symmetry and shadow of the near-extremal Kerr black holePrincipal Investigator

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[Journal Article] Periapsis shifts in dark matter distribution around a black hole2023

Author(s)

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[Journal Article] General formulae for the periapsis shift of a quasi-circular orbit in static spherically symmetric spacetimes and the active gravitational mass density2023

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[Journal Article] Periapsis shifts in dark matter distribution with a dense core2022

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[Journal Article] Photon escape in the extremal Kerr black hole spacetime2022

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[Journal Article] Photon emission from inside the innermost stable circular orbit2021

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[Journal Article] Stable circular orbits in caged black hole spacetimes2021

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[Journal Article] Photon surfaces in less symmetric spacetimes2021

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[Journal Article] Stable circular orbits in Kaluza-Klein black hole spacetimes2021

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[Journal Article] Complete classification of photon escape in the Kerr black hole spacetime2021

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[Journal Article] Chaos in a generalized Euler’s three-body problem2021

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[Journal Article] Escape probability of a photon emitted near the black hole horizon2020

igata takahisa 伊形尚久

IGATA Takahisa 伊形尚久