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Turbulent Supernovae Explosion

Research Project

Project/Area Number 18H01212
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Review Section Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
Research InstitutionThe University of Tokyo

Principal Investigator

横井 喜充  東京大学, 生産技術研究所, 助教 (50272513)

Co-Investigator(Kenkyū-buntansha) 政田 洋平  愛知教育大学, 教育学部, 准教授 (30590608)
滝脇 知也  国立天文台, 科学研究部, 助教 (50507837)
Project Period (FY) 2018-04-01 – 2022-03-31
Project Status Granted (Fiscal Year 2021)
Budget Amount *help
¥17,160,000 (Direct Cost: ¥13,200,000、Indirect Cost: ¥3,960,000)
Fiscal Year 2021: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2020: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2019: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2018: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
Keywords超新星爆発 / 乱流 / 乱流モデル / 超新星数値シミュレーション / 恒星対流 / 超新星 / シミュレーション / 圧縮性乱流 / 乱流輸送モデル / 対流 / 衝撃波 / 乱流輸送 / モデル / ローカル・シミュレーション / グローバル・シミュレーション
Outline of Annual Research Achievements

星の進化とその最終段階である超新星爆発は,恒星内部のダイナミクスと非線型相互作用で結びついた乱流の輸送に支配される.しかし,通常の乱流モデルは, 混合距離理論に代表されるように,その場限りで経験的に与えられるものにとどまっている.本研究では,まず強非線型かつ非一様な乱流の理論 を星の進化を記述する方程式系に適用し,応力(運動量輸送),乱流質量流束,乱流熱流束などの乱流相関を解析した.その結果を用いて,経験的ではなく基礎方程式に基づいた乱流モデルの構築を行った.そこでは平均場と乱流統計量の非線型ダイナミクスを同時に解くことで,乱流輸送係数も含めて自己無撞着に場 が解かれる.これは,混合距離理論で,乱流輸送の大きさをパラメータとして与える従来の天体物理学乱流モデルとは一線を画する.

その知見をもとに,回転,密度変動,磁場などの印可パラメータを変えつつ,簡単形状の局所的シミュレーションでモデルを検証・発展させている. さらに,その発展したモデルを用いて超新星の大域的シミュレーションを行う.直接数値計算と乱流モデル計算を比較することで,三次元の乱流効果を一次元の方程式に落とし込み,簡略化された超新星の標準モデルを開発する.現在,この三次元グローバル数値計算の結果と二次元のローカルシミュレーションの結果との比較を鋭意行っている. このように,(i)基礎方程式に基づく乱流モデルの開発; (ii)局所シミュレーションによる乱流モデルの検証と発展; (iii)発展した乱流モデルの大域 的シミュレーション; (iv)低次元簡略化乱流モデルの開発;という研究段階のうち,(i)と(ii)まで,順調に進んでおり,その成果は幾つかの学術論文として 公刊されている.

Current Status of Research Progress
Current Status of Research Progress

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

Reason

理由 研究段階の前半部分のそれぞれで進展が見られた. (i)基礎方程式に基づく乱流モデルの開発:密度・ 速度・温度などの非一様性,衝撃波,さらには回転や磁場など多くの時間スケールを扱う理論枠組で,乱流 相関を評価し,乱流輸送の表式を求めた. (ii)局所シミュレーションによる乱流モデルの検証と発展:直接数値計算と乱流モデルの結果を比較し,モデルの妥当性を検証している.密度勾配,回転角速 度の強さ,それらの幾何形状といったシミュレーションの設定を変えることで,個々の物理要素とその組み合わせがどのように対流の性質を変え,結果として熱輸送にどのような影響を与え,それはどのような条件で起きるのかを調べている.それらの結果から,乱流輸送の表現にとって最も重要な時間スケールの評価について知見を得ている.例えば,乱流の時間スケールの表現には,最も簡単な,乱流エネルギーK=<u’^2>/2と混合距離L;の組み合わせL K^(1/2) ,乱流エネル ギーKとエネルギー散逸率εの組み合わせK/ε,といった類のものから,さらに他の物理過程の時間スケールを組み合わせたものまで,さまざまな表現法が考えられる. また,(iii)発展した乱流モデルのグローバル・シミュレーションでは,直接数値計算を用いてレイノルズ応力の空間分布を調べた.その分布から,乱流モデルが不可欠な半径領域を同定することに成功した.これにより,乱流理論に基づく自己無撞着な乱流モデルを大域シミュレーションに適用する領域が明確となっ ている.さらに,星の対流層を模した局所シミュレーションで,放射冷却などによって星の表層で降下する構造的流れ(プルーム)が存在する場合の星の対流構造を解析した.プルームによって,表層近傍の上部や中層で乱流輸送が飛躍的に増大する現象を,乱流の非平衡効果で初めて説明し,その効果を組み入れた乱流モデルを構築した.

Strategy for Future Research Activity

これまでの成果をもとに,研究段階の後半部分について研究を推進する. (iii)発展した乱流モデルの大域的シミュレーション: 上の段階までで発展させてきた乱流モデルを組み入れた大域的シミュレーションを行いつつあ る.特に,段階(ii)の局所シミュレーションで得られた知見を基に,大域シミュレーションの物理パラメータを変化させ,どのような条件下で超新星爆発が起きるかを精査する. (iv)低次元簡略化乱流モデルの開発: 大域と局所の両シミュレーションで,三次元の直接数値計算の結果と乱流モデルによる数値計算の比較を行 い,二次元や一次元といったより低次元の計算でも乱流の効果を正しく取り入れることで超新星爆発を正しく再現できるように,簡略化した乱流モデルを開発する. シミュレーションに関しては,局所シミュレーション,大域シミュレーションともに, 基本的な幾何形状の設定はこれまでに研究してきたものと同じものを用いることができる.乱流の効果を表現する乱流モデルの部分は,上述した超新星爆発の乱流モデル部分を計算コードに組み入れる必要がある.シミュレーションから乱流モデルへのフィードバック,また三次元シミュレーション結果の低次元 簡易モデルへの落とし込みにあたっては,研究チーム内での頻繁かつ徹底的な議論が必要になると予想されるので,相互訪問するための旅費を十分確保する.研究チームの各人のこれまでの研究結果および資源や経験を基本的には利用可能なので,今回の組織で上述の研究段階を十分速やかに実行できると期待される.ただし,個々の段階(特に局所および大域シミュレー ション)では,計算環境に加えて計算実行を補佐する人的資源も必要になるので,数値コードの開発もできる博士研究員を一定期間雇用するなどし,研究を強力に推進する.

Report

(2 results)
  • 2019 Annual Research Report
  • 2018 Annual Research Report

Research Products

(36 results)

All 2021 2020 2019 2018

All Journal Article (21 results) (of which Int'l Joint Research: 21 results,  Peer Reviewed: 21 results,  Open Access: 8 results) Presentation (15 results) (of which Int'l Joint Research: 10 results,  Invited: 4 results)

  • [Journal Article] A new gravitational-wave signature of low-T/|W| instability in rapidly rotating stellar core collapse2020

    • Author(s)
      Shibagaki Shota , Kuroda Takami , Kotake Kei , Takiwaki Tomoya
    • Journal Title

      Monthly Notices of the Royal Astronomical Society: Letters

      Volume: 493

    • DOI

      10.1093/mnrasl/slaa021

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Detectability of collective neutrino oscillation signatures in the supernova explosion of a 8.8 solar mass star2020

    • Author(s)
      Sasaki Hirokazu、Takiwaki Tomoya、Kawagoe Shio、Horiuchi Shunsaku、Ishidoshiro Koji
    • Journal Title

      Physical Review D

      Volume: 101 Pages: 063027-063027

    • DOI

      10.1103/physrevd.101.063027

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Propagation, cocoon formation, and resultant destabilization of relativistic jets2019

    • Author(s)
      Jin Matsumoto; Youhei Masada
    • Journal Title

      Monthly Notices of the Royal Astronomical Society

      Volume: 490 Pages: 4271-4280

    • DOI

      10.1093/mnras/stz2821

    • Related Report
      2019 Annual Research Report 2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Neutrino-dominated Accretion Flows with Magnetic Prandtl Number-dependent MRI-driven Turbulence2019

    • Author(s)
      Norita Kawanaka; Youhei Masada
    • Journal Title

      The Astrophysical Journal

      Volume: 881 Pages: 138-138

    • DOI

      10.3847/1538-4357/ab2e71

    • Related Report
      2019 Annual Research Report 2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] On the occurrence of fast neutrino flavor conversions in multidimensional supernova models2019

    • Author(s)
      Abbar Sajad , Duan Huaiyu , Sumiyoshi Kohsuke , Takiwaki Tomoya , Volpe Maria Cristina
    • Journal Title

      Physical Review D

      Volume: 100 Pages: 043004-043004

    • DOI

      10.1103/physrevd.100.043004

    • Related Report
      2019 Annual Research Report 2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Analysis of fast turbulent reconnection with self-consistent determination of turbulence timescale2019

    • Author(s)
      Widmer F.、Buechner J.、Yokoi N.
    • Journal Title

      Physics of Plasmas

      Volume: 26 Pages: 102112-102112

    • DOI

      10.1063/1.5109020

    • Related Report
      2019 Annual Research Report 2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Turbulence, transport and reconnection2019

    • Author(s)
      Yokoi, N.
    • Journal Title

      CISM International Centre for Mechanical Sciences

      Volume: 591 Pages: 177-265

    • DOI

      10.1007/978-3-030-16343-3_6

    • Related Report
      2019 Annual Research Report 2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Cross helicity sign reversals in the dissipative scales of magnetohydrodynamic turbulence2019

    • Author(s)
      Titov, V., Stepanov, R., Yokoi, N., Verma, M., Samtaney, R.
    • Journal Title

      Magnetohydrodynamics

      Volume: 55 Pages: 225-231

    • NAID

      130007584991

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Multiple-scale analysis of the strong compressibility effects on transport in magnetohydrodynamic turbulence2019

    • Author(s)
      Yokoi, N.
    • Journal Title

      Progress in Turbulence

      Volume: VIII Pages: 241-246

    • DOI

      10.1007/978-3-030-22196-6_38

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Dependence of the outer boundary condition on protoneutron star asteroseismology with gravitational-wave signatures2019

    • Author(s)
      Sotani Hajime , Kuroda Takami , Takiwaki Tomoya , Kotake Kei
    • Journal Title

      Physical Review D

      Volume: 99 Pages: 123024-123024

    • DOI

      10.1103/physrevd.99.123024

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] One-, Two-, and Three-dimensional Simulations of Oxygen-shell Burning Just before the Core Collapse of Massive Stars2019

    • Author(s)
      Yoshida Takashi、Takiwaki Tomoya、Kotake Kei、Takahashi Koh、Nakamura Ko、Umeda Hideyuki
    • Journal Title

      The Astrophysical Journal

      Volume: 881 Pages: 16-16

    • DOI

      10.3847/1538-4357/ab2b9d

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Long-term simulations of multi-dimensional core-collapse supernovae: Implications for neutron star kicks2019

    • Author(s)
      Nakamura Ko , Takiwaki Tomoya , Kotake Kei
    • Journal Title

      Publications of the Astronomical Society of Japan

      Volume: 71 Pages: 80-80

    • DOI

      10.1093/pasj/psz080

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Determination of properties of protoneutron stars toward black hole formation via gravitational wave observations2019

    • Author(s)
      Sotani Hajime、Sumiyoshi Kohsuke
    • Journal Title

      Physical Review D

      Volume: 100 Pages: 083008-083008

    • DOI

      10.1103/physrevd.100.083008

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Supernova Ejecta Interacting with a Circumstellar Disk. I. Two-dimensional Radiation-hydrodynamic Simulations2019

    • Author(s)
      Suzuki Akihiro、Moriya Takashi J.、Takiwaki Tomoya
    • Journal Title

      The Astrophysical Journal

      Volume: 887 Pages: 249-249

    • DOI

      10.3847/1538-4357/ab5a83

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Generation of a large-scale magnetic field in a convective full-sphere cross-helicity dynamo2018

    • Author(s)
      Pipin, V. V., Yokoi, N.
    • Journal Title

      The Astrophysical Journal

      Volume: 859 Pages: 18-18

    • DOI

      10.3847/1538-4357/aabae6

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Path integrals for mean-field equations in nonlinear dynamos2018

    • Author(s)
      Sokoloff, D., Yokoi, N.
    • Journal Title

      Journal of Plasma Physics

      Volume: 84 Pages: 735840307-735840307

    • DOI

      10.1017/s0022377818000521

    • NAID

      130006322029

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Turbulent dynamos beyond the heuristic modeling: Helicities and density variance2018

    • Author(s)
      Yokoi, N.
    • Journal Title

      AIP CP Series

      Volume: 1993 Pages: 020010-020010

    • DOI

      10.1063/1.5048720

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Electromotive force in strongly compressible magnetohydrodynamic turbulence2018

    • Author(s)
      Yokoi, N.
    • Journal Title

      Journal of Plasma Physics

      Volume: 84 Pages: 735840501-735840501

    • DOI

      10.1017/s0022377818000727

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Mass and internal-energy transports in strongly compressible magnetohydrodynamic turbulence2018

    • Author(s)
      Yokoi, N.
    • Journal Title

      Journal of Plasma Physics

      Volume: 84 Pages: 775840603-775840603

    • DOI

      10.1017/s0022377818001228

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Global comparison of core-collapse supernova simulations in spherical symmetry2018

    • Author(s)
      O’Connor Evan、Bollig Robert、Burrows Adam、Couch Sean、Fischer Tobias、Janka Hans-Thomas、Kotake Kei、Lentz Eric J、Liebend?rfer Matthias、Messer O E Bronson、Mezzacappa Anthony、Takiwaki Tomoya、Vartanyan David
    • Journal Title

      Journal of Physics G: Nuclear and Particle Physics

      Volume: 45 Pages: 104001-104001

    • DOI

      10.1088/1361-6471/aadeae

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Chiral magnetohydrodynamic turbulence in core-collapse supernovae2018

    • Author(s)
      Masada Youhei、Kotake Kei、Takiwaki Tomoya、Yamamoto Naoki
    • Journal Title

      Physical Review D

      Volume: 98 Pages: 083018-083018

    • DOI

      10.1103/physrevd.98.083018

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Presentation] Magnetoclinicity Instability2021

    • Author(s)
      Yokoi, Nobumitsu
    • Organizer
      iTi Conference on Turbulence
    • Related Report
      2019 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Unappreciated helicity effects in magnetohydrodynamic turbulence2021

    • Author(s)
      Yokoi, Nobumitsu
    • Organizer
      Online Advanced Program on Helicities in Astrophysics and Beyond
    • Related Report
      2019 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] 超新星爆発における輸送現象2021

    • Author(s)
      滝脇知也
    • Organizer
      第37回プラズマ核融合学会年会
    • Related Report
      2019 Annual Research Report
  • [Presentation] 太陽熱対流の非局所性とその輸送ダイナミクスへの影響:理論モデルの検討2021

    • Author(s)
      政田洋平
    • Organizer
      第37回プラズマ核融合学会年会
    • Related Report
      2019 Annual Research Report
  • [Presentation] Magnetoclinicity: Density variance effects in large-scale instability in magnetohydrodynamic turbulence2020

    • Author(s)
      Yokoi, Nobumitsu
    • Organizer
      European Geosciences Union (EGU) General Assembly
    • Related Report
      2019 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Statistical theories of turbulent transport and the prospects of applying such theories in the modeling of astrophysical convection2020

    • Author(s)
      Yokoi, Nobumitsu
    • Organizer
      The Shifting Paradigm of Stellar Convection: From Mixing Length Concepts to Realistic Turbulence Modeling
    • Related Report
      2019 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Exploration of transport enhancement and suppression in turbulence: Helicity effects2019

    • Author(s)
      Yokoi, N.
    • Organizer
      Sensing, Mining and Modeling of Wave, Flow and Turbulence, RIAM, Kyushu Univ., Fukuoka, 31 January - 1 February 2019
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Multiple-scale analysis of turbulent transport in strongly compressible magnetohydrodynamic plasmas2019

    • Author(s)
      Yokoi , N.
    • Organizer
      International symposium on recent progress in heliospheric physics by direct measurements of unexplored space plasmas, Institute of Space and Earth Environmental Research (ISEE), Nagoya University
    • Related Report
      2018 Annual Research Report
  • [Presentation] Focus event, summary and discussion on topic 1: Role, importance, and evolution of helicity N. Yokoi Solar Helicities in Theory and Observations: Implications for Space Weather and Dynamo Theory, Nordic Institute for Theoretical Physics (NORDITA), Stockholm, 4-29 March 2019, 1-5-22019

    • Author(s)
      Yokoi, N.
    • Organizer
      Solar Helicities in Theory and Observations: Implications for Space Weather and Dynamo Theory, Nordic Institute for Theoretical Physics (NORDITA), Stockholm, 4-29 March 2019
    • Related Report
      2018 Annual Research Report
  • [Presentation] Turbulent transport in strongly compressible magnetohydrodynamic flows2019

    • Author(s)
      Yokoi, N.
    • Organizer
      Solar Helicities in Theory and Observations: Implications for Space Weather and Dynamo Theory, Nordic Institute for Theoretical Physics (NORDITA), Stockholm, 4-29 March 2019
    • Related Report
      2018 Annual Research Report
  • [Presentation] Multiple-scale analysis of turbulent transport in strongly compressible magnetohydrodynamic flows2018

    • Author(s)
      Yokoi, N.
    • Organizer
      Proceedings of European Geosciences Union General Assembly Meeting 2018 (Vienna, Austria)
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Turbulent dynamo research beyond heuristic modelling2018

    • Author(s)
      Yokoi, N.
    • Organizer
      Theory and Simulation of Solar System Plasmas (TSSSP) Symposium: From space, solar and laboratory plasmas to plasma astrophysics, Goettingen, 18-19 June 2018
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Multiple-scale analysis of the strongly compressible effects on transport in magnetohydrodynamic turbulence2018

    • Author(s)
      Yokoi, N.
    • Organizer
      iTi Conference on Turbulence VIII, Bertinoro, 5-7 September 2018
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Multiple-scale analysis of turbulent transports in highly compressible magnetohydrodynamic plasma flows2018

    • Author(s)
      Yokoi, N.
    • Organizer
      2nd Asia-Pacific Conference on Plasma Physics (AAPPS-DPP2018), Kanazawa, 12-17 November 2018
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Effective mass and energy fluxes in strongly compressible magnetohydrodynamic turbulence: Density-variance and compressive cross-helicity effects2018

    • Author(s)
      Yokoi, N.
    • Organizer
      American Geophysical Society Fall Meeting 2018, Washington D.C., Dec. 2018
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research

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Published: 2018-04-23   Modified: 2021-12-27  

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