Theory for the Formation of Star Clusters and the Evolution of Our Galaxy

• Project Area: A Paradigm Shift by a New Integrated Theory of Star Formation: Exploring the Expanding Frontier of Habitable Planetary Systems in Our Galaxy
• Project/Area Number: 18H05437
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Nagoya University
• Principal Investigator: 犬塚 修一郎 名古屋大学, 理学研究科, 教授 (80270453)
• Co-Investigator(Kenkyū-buntansha): 長島 雅裕 文教大学, 教育学部, 教授 (20342628) ; 諏訪 雄大 京都産業大学, 理学部, 准教授 (40610811) ; 千葉 柾司 東北大学, 理学研究科, 教授 (50217246) ; 松本 倫明 法政大学, 人間環境学部, 教授 (60308004) ; 塚本 裕介 鹿児島大学, 理工学域理学系, 助教 (70748475)
• Project Period (FY): 2018-06-29 – 2023-03-31
• Project Status: Granted (Fiscal Year 2020)
• Budget Amount: ¥122,200,000 (Direct Cost: ¥94,000,000、Indirect Cost: ¥28,200,000); Fiscal Year 2021: ¥24,180,000 (Direct Cost: ¥18,600,000、Indirect Cost: ¥5,580,000); Fiscal Year 2020: ¥27,430,000 (Direct Cost: ¥21,100,000、Indirect Cost: ¥6,330,000); Fiscal Year 2019: ¥24,180,000 (Direct Cost: ¥18,600,000、Indirect Cost: ¥5,580,000); Fiscal Year 2018: ¥22,230,000 (Direct Cost: ¥17,100,000、Indirect Cost: ¥5,130,000)
• Keywords: 星形成 / 星団形成 / 原始惑星系円盤 / 銀河進化 / 重元素量 / 原始惑星系円盤形成

Outline of Annual Research Achievements

長島は自身が構築した銀河形成モデルを用いて銀河の光度関数等の観測を再現するような星形成パラメータを調べ，銀河スケールで平均化した場合の星形成のタイムスケールについては，銀河系程度の銀河については約140～220 Myr程度であることを示した．
千葉は2年前に公開された恒星のアストロメトリカタログGaia DR2ならびにすばる望遠鏡の超広視野カメラHSCなどによる観測データの解析を実施し，銀河系円盤の新しい動力学構造の発見に至ったと共に，そのような銀河系円盤内のダイナミクスと星形成過程に対して，外部からの力学相互作用によって大きな影響を与える銀河系衛星銀河の諸性質に関し重要な研究成果が得た．
松本は周連星円盤の数値シミュレーションを遂行し，周連星円盤に現れるこれらの特徴的な構造が周連星円盤と連星との重力相互作用の結果であることを明らかにした．連星の質量比、ガスの温度、ガスの角運動量を幅広く変えたモデルを多数計算し，周連星円盤の構造がこれらのパラメータにどのように依存するかを調べた．その結果，ギャップ・渦状腕・非対称な円盤などの構造は原始連星に共通の性質であることを示した．
塚本は詳細な電離・再結合過程を含む高速の非理想輻射磁気流体力学シミュレーション法を開発している．
諏訪は銀河進化における超新星爆発の影響およびそこからの重元素放出を明らかにすることを目指している．特に現在は超新星爆発における元素合成に焦点を絞って研究を進めている．これまでの研究で，超新星爆発の中心部の活動性と放射性同位体であるニッケル56の生成量に強い関係があることを明らかにした．
研究代表者の犬塚は研究全体を統括した．まず初年度である2018年度は，ガス質量の割に星形成活動が不活発な銀河中心領域での星形成活動を詳細に解析して論文としてまとめ，今後の観測により調査する重要点を列挙した．

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

各研究分担者は本課題に解答を与えるべく順調に研究を進めている．査読付き論文としての成果発表のリストの充実度から見て，十分な実績内容だと判断する．

Strategy for Future Research Activity

各研究分担者は現在進めている研究をこれまで通り発展させる．また，現在，早いテンポで進みつつある星形成過程の理解を，専門が異なる計画研究分担者となるべく共有することをさらに進める．なお，コロナウィルス問題のため，雇用したい海外の博士研究者を雇用するのが難しくなっているので，その対応策を研究分担者とも相談しながら進める予定である．

Research Products

• [Int'l Joint Research] CEA/CNRS Saclay(フランス)
• [Journal Article] The Early Stage of Molecular Cloud Formation by Compression of Two-phase Atomic Gases (2019)
  • Author(s): Iwasaki, Kazunari; Tomida, Kengo; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro
  • Journal Title: The Astrophysical Journal Volume: 873 Pages: 21-27
  • DOI: 10.3847/1538-4357/ab02ff
  • Peer Reviewed
• [Journal Article] The Role of Magnetic Field in Molecular Cloud Formation and Evolution (2019)
  • Author(s): Hennebelle Patrick、Inutsuka Shu-ichiro
  • Journal Title: Frontiers in Astronomy and Space Sciences Volume: 6
  • DOI: 10.3389/fspas.2019.00005
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Structure of a Protobinary System: An Asymmetric Circumbinary Disk and Spiral Arms (2019)
  • Author(s): Matsumoto Tomoaki、Saigo Kazuya、Takakuwa Shigehisa
  • Journal Title: The Astrophysical Journal Volume: 871 Pages: 36-36
  • DOI: 10.3847/1538-4357/aaf6ab
  • Peer Reviewed
• [Journal Article] A New HLLD Riemann Solver with Boris Correction for Reducing Alfven Speed (2019)
  • Author(s): Matsumoto, Tomoaki; Miyoshi, Takahiro; Takasao, Shinsuke
  • Journal Title: The Astrophysical Journal Volume: 874 Pages: 37-37
  • DOI: 10.3847/1538-4357/ab05cb
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The New Numerical Galaxy Catalogue (ν2GC): properties of active galactic nuclei and their host galaxies (2019)
  • Author(s): Shirakata, H., Okamoto, T., Kawaguchi, T., Nagashima, M., Ishiyama, T., Makiya, R., Kobayashi, M. A. R., Enoki, M., Oogi, T., Okoshi, K.
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 482 Pages: 48464873-48464873
  • DOI: 10.1093/mnras/sty2958
  • Peer Reviewed / Open Access
• [Journal Article] Importance of 56Ni production on diagnosing explosion mechanism of core-collapse supernova (2019)
  • Author(s): Suwa Yudai、Tominaga Nozomu、Maeda Keiichi
  • Journal Title: Monthly Notices of the Royal Astronomical Society, Volume 483, Issue 3, p.3607-3617 Volume: 483 Pages: 3607-3617
  • DOI: 10.1093/mnras/sty3309
  • Peer Reviewed / Open Access
• [Journal Article] Possible Counterrotation between the Disk and Protostellar Envelope around the Class I Protostar IRAS 04169+2702 (2019)
  • Author(s): Takakuwa Shigehisa、Tsukamoto Yusuke、Saigo Kazuya、Saito Masao
  • Journal Title: Astrophysical Journal Volume: 865 Pages: 51-51
  • DOI: 10.3847/1538-4357/aadb93
  • Peer Reviewed
• [Journal Article] The formation of massive molecular filaments and massive stars triggered by a magnetohydrodynamic shock wave (2018)
  • Author(s): Inoue, T., Hennebelle, P., Fukui, Y., Matsumoto, T., Iwasaki, K., & Inutsuka, S. -i.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70
  • DOI: 10.1093/pasj/psx089
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Star formation induced by cloud-cloud collisions and galactic giant molecular cloud evolution (2018)
  • Author(s): Kobayashi, M. I. N., Kobayashi, H., Inutsuka, S. -i., & Fukui, Y.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70
  • DOI: 10.1093/pasj/psy018
  • Peer Reviewed / Open Access
• [Journal Article] A Fast and Accurate Method of Radiation Hydrodynamics Calculation in Spherical Symmetry (2018)
  • Author(s): Stamer Torsten、Inutsuka Shu-ichiro
  • Journal Title: The Astronomical Journal Volume: 155 Pages: 253-253
  • DOI: 10.3847/1538-3881/aac023
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The diverse lives of massive protoplanets in self-gravitating discs (2018)
  • Author(s): Stamatellos Dimitris、Inutsuka Shu-ichiro
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 477 Pages: 3110-3135
  • DOI: 10.1093/mnras/sty827
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Molecular filament formation and filament-cloud interaction: Hints from Nobeyama 45 m telescope observations (2018)
  • Author(s): Arzoumanian, Doris; Shimajiri, Yoshito; Inutsuka, Shu-ichiro; Inoue, Tsuyoshi; Tachihara, Kengo
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70
  • DOI: 10.1093/pasj/psy095
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Does Misalignment between Magnetic Field and Angular Momentum Enhance or Suppress Circumstellar Disk Formation? (2018)
  • Author(s): Tsukamoto Y.、Okuzumi S.、Iwasaki K.、Machida M. N.、Inutsuka S.
  • Journal Title: The Astrophysical Journal Volume: 868 Pages: 22-22
  • DOI: 10.3847/1538-4357/aae4dc
  • Peer Reviewed / Open Access
• [Journal Article] Toward understanding the origin of asteroid geometries (2018)
  • Author(s): Sugiura K.、Kobayashi H.、Inutsuka S.
  • Journal Title: Astronomy and Astrophysics Volume: 620
  • DOI: 10.1051/0004-6361/201833227
  • Peer Reviewed
• [Journal Article] Radiation-hydrodynamic Simulations of Spherical Protostellar Collapse for Very Low-mass Objects (2018)
  • Author(s): Stamer Torsten、Inutsuka Shu-ichiro
  • Journal Title: The Astrophysical Journal Volume: 869 Pages: 179-179
  • DOI: 10.3847/1538-4357/aaee81
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Properties of an accretion disc with a power-law stress?pressure relationship (2018)
  • Author(s): Shadmehri Mohsen、Khajenabi Fazeleh、Dib Sami、Inutsuka Shu-ichiro
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 481 Pages: 5170-5179
  • DOI: 10.1093/mnras/sty2656
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The Exchange of Mass and Angular Momentum in the Impact Event of Ice Giant Planets: Implications for the Origin of Uranus (2018)
  • Author(s): Kurosaki Kenji、Inutsuka Shu-ichiro
  • Journal Title: The Astronomical Journal Volume: 157 Pages: 13-13
  • DOI: 10.3847/1538-3881/aaf165
  • Peer Reviewed
• [Journal Article] Structure of the Milky Way stellar halo out to its outer boundary with blue horizontal-branch stars (2018)
  • Author(s): Fukushima Tetsuya、Chiba Masashi、Homma Daisuke、Okamoto Sakurako、Komiyama Yutaka、Tanaka Masayuki、Tanaka Mikito、Arimoto Nobuo、Matsuno Tadafumi
  • Journal Title: Publication of Astronomical Society of Japan Volume: 70 Pages: 1-1
  • DOI: 10.1093/pasj/psy060
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The Missing Satellite Problem Outside of the Local Group. I. Pilot Observation (2018)
  • Author(s): Tanaka Masayuki、Chiba Masashi、Hayashi Kohei、Komiyama Yutaka、Okamoto Takashi、Cooper Andrew P.、Okamoto Sakurako、Spitler Lee
  • Journal Title: Astrophysical Journal Volume: 865 Pages: 125-125
  • DOI: 10.3847/1538-4357/aad9fe
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] The Formation and Early Evolution of Protoplanetary Disks (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: From Prestellar Cores to Solar Nebulae
  • Int'l Joint Research / Invited
• [Presentation] Review on the role of magnetic field in the formation and evolution of filamentary molecular clouds (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: Magnetic fields along the star-formation sequence: bridging polarization-sensitive views
  • Int'l Joint Research / Invited
• [Presentation] The formation and evolution of filamentary molecular clouds and star formation (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: The Wonders of Star Formation
  • Int'l Joint Research
• [Presentation] An Origin of Multiple Rings in Protoplanetary Disks: Non-Linear Development of Secular Gravitational Instability in Protoplanetary Disks (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: The Eighth East Asian Numerical Astrophysics Meeting
  • Int'l Joint Research
• [Presentation] The Formation of Magnetized Molecular Clouds and Subsequent Star Formation (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: First TagKASI International Conference: "Cosmic Dust and Magnetism"
  • Int'l Joint Research / Invited
• [Presentation] The Study of Star Formation with ALMA (2018)
  • Author(s): Shu-ichiro Inutsuka
  • Organizer: East Asian ALMA Science Workshop 2018
  • Int'l Joint Research / Invited
• [Remarks] 犬塚修一郎のホームページ
  • URL: http://www.astro-th.phys.nagoya-u.ac.jp/~inutsuka/index_j.html
• [Remarks] 新学術領域研究「新しい星形成理論によるパラダイムシフト」
  • URL: http://star-planet.jp/
• [Remarks] Protostars and Planets VII
  • URL: http://ppvii.org/
• [Remarks] 星・惑星形成ゼミ
  • URL: https://sites.google.com/view/spfseminar/home
• [Funded Workshop] Interstellar filament paradigm: On their formation, evolution, and role in star formation (2018)