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R-process Elements in the First Generation Stars and High-redshift Objects and the Galactic-and Cosmic-Age Problem.

Research Project

Project/Area Number 10640236
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Astronomy
Research InstitutionNational Astronomical Observatory

Principal Investigator

KAJINO Toshitaka  National Astronomical Observatory Divisin of Theoretical Astrophysics Associate Professor, 理論天文学研究系, 助教授 (20169444)

Co-Investigator(Kenkyū-buntansha) CHIBA Masashi  National Astronomical Observatory Division of Astrometry and Celestial Mechanics Associate professor, 位置天文・天体力学研究系, 助教授 (50217246)
YOSHII Yuzuru  University of Tokyo Institute of Astronomy, Professor, 天文教育研究センター, 教授 (00158388)
NOMOTO Kenichi  University of Tokyo School of Science, Professor, 大学院・理学系研究科, 教授 (90110676)
TOKI Hiroshi  Osaka University, Research Center for Nuclear Physics, Professor, 核物理研究センター, 教授 (70163962)
SADAKANE Kozo  Osaka Kyoiku University, Faculty of Education, Professor, 教育学部, 教授 (20110794)
谷畑 勇 (谷畑 勇夫)  理化学研究所, 加速器科学研究室, 主任研究員 (10089873)
Project Period (FY) 1998 – 1999
Project Status Completed (Fiscal Year 2000)
Budget Amount *help
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2000: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1999: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1998: ¥1,000,000 (Direct Cost: ¥1,000,000)
KeywordsNucleo-cosmochronology / Supernova Explosion / Neutrino / Neutron Star / R-process / R-過去 / r-過程 / γ-過程 / トリウム / ホットバブル / 一般相対論
Research Abstract

Observational study of the r-process elements was one of the utlimate purposes in this project, and it has just started in the year 2000 with the construction of SUBARU TELESCOPE which is equipped with High-Dispersion-Spectrograph (HDS) at the top of Mt.Kea. We have already carried out several test observations of SUBARU-HDS, which proves to work very well as we designed. Using this spectrograph, several metal-deficient halo stars have already been observed in order to detect metal absorption lines from Th232 (half life 14.1 Gy), U238 (4.5 Gy), Re187 (43.5 Gy), and many others. Data analysis is now underway. Theoretical studies of the r-process nucleosynthesis in supernova explosions also have been carried out to reach deep understanding of the nucleosynthesis mechanism. Actinoids are ideal heavy radioactive nuclei whose half life is of order of cosmic age. In this project, it was theoretically clarified that most heavy r-process elements, including some amounts of actinoids, are produced in explosive nucleosynthesis associated with Type II SN explosions. Dependence of the calculated yields of these elements on the physical conditions of stellar environments were studied in detail : It was clarified the relation between r-process abundance yields and physical parameters such as neutrino flux from the center of proto-neutron star, mass and radius of the neutron star, entropy and dynamic time scale which are closely related to the neutrino heating proceses in the neutrino-
driven winds.

Report

(4 results)
  • 2000 Annual Research Report   Final Research Report Summary
  • 1999 Annual Research Report
  • 1998 Annual Research Report
  • Research Products

    (37 results)

All Other

All Publications (37 results)

  • [Publications] T.Kajino: "Impact of Faw Body Reactions on Explosive Nucleo-synthesis : The big-Bang and Supernovae."Fers-Body Systems, Supplement. 12. 80-85 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] K.Otsuki: "The General Relativistic Effects on nantrino-driren winds from yong, but neutron stars and r-process model synthesis"Astrophysical Journal. 533. 424-439 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] P.A.Maggali: "A Spectroscopic Analysis of Enargetic Type IC Hypernora SN 1997 ef."Astrophysical Journal. 545. 407-419 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.Tsujimoto: "Probing the site for R-process Nuclear synthesis with Abundances of Barium and magnesium…"Astrophysical Journal. 531. L33-L36 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] M.Chiba: "Kinematics of Metal-Poor Stars in the Galaxy III. Formation of the Stallar Hale and Thick Disk…"Astrophysical Journal. 119. 2843-2865 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] J.Nakashima: "Period Measurement of AGB Stars in Outers Galation Disk."Putl.Astron.Soc.Japan. 52. 275-294 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.Kajino and M.Orito: "Neutrinos and Big-Bang Nucleosynthesis."Nucl.Phys.. A629. 538c-544c (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.-K.Suzuki, Y.Yoshii and T.Kajino: "Evolution of beryllium and boron in the inhomogeneous early Galaxy."Astrophys.J.. 522. L125-L128 (1999)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] A.Tokuhisa and T.Kajino: "Meson synchrotron emission from central engines of gamma-ray bursts with strong magnetic fields."Astrophys.J.. 525. L117-L120 (1999)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] K.Otsuki, H.Tagoshi, T.Kajino and S.Wanajo: "The general relativistic effects on neutrino-driven winds from young, hot neutron stars and the r-process nucleosynthesis."Astrophys.J.. 533. 424-439 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.Kajino, K.Otsuki, H., S.Wanajo, Mo.Orito, and G.M.Mathews: "Impact of A Few Body Reactions on Explosive Nucleosynthesis : Supernovae and Big-Bang."Few-Body Systems Suppl.. 12. 80-85 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] S.G.Ryan, T.C.Beers, T.Kajino, and K.Rosolankova: "Ultra-Lithium-Deficient Halo Stars and Blue Stragglers : A Unifying View."Astrophys.J.. 547. 231-239 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] M.Famiano, J.Vandegriff, R.N.Boyd, T.Kajino, and P.Osmer: "Production of 2H and 3He from Interactions between Jets and Clouds."Astrophys.J.Lett.. 547. L21-L24 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] S.G.Ryan, T.Kajino, T.C.Beers, T-K.Suzuki, D.Romano, F.Matteucci, and K.Rosolankova: "Abundances and Evolution of Lithium in the Galactic Halo and Disk."Astrophys.J.. 549. 55-71 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] S.Wanajo, T.Kajino, and G.J.Mathews, and K.Otsuki: "The r-process in netrino-driven winds from nascent icompacti neutron stars of core-collapse supernovae."Astrophys.J.. 10 isuue (in Press). (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.Kajino, S.Wanajo, G.J.Mathews: "R-process nucleosynthesis in core-collapse supernova explosion."Nucl.Phys.A. (in press). (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] M.Orito, T.Kajino, G.J.Mathews, and R.N.Boyd: "Primordial Nucleosynthesis and Neutrinos with Mass and Degeneracy."Nucl.Phys.A.. (in press). (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] M.Teraswas, K.Sumiyoshi, T.Kajino, I.Tanihata, G.J.Mathews, and K.Langanke: "New Nuclear Reaction Flow during r-Process Nucleosynthesis in Supernovae : The Critical Role of Light Neutron-Rich Nuclei."Nucl.Phys.A.. ( in press). (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] M.Orito, T.Kajino, G.J.Mathews, and R.N.Boyd: "Neutrino Degeneracy and Decoupling : New Limits from Primordial Nucleo-synthesis and the Cosmic Microwave Background."Astrophys.J.. (in press). (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2000 Final Research Report Summary
  • [Publications] T.Kajino: "Impact of Few Body Reactions on Explosive Nucleosynthesis : The Big-Bang and Supernovae."Few-Body Systems, Supplement. 12. 80-85 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] K.Otsuki: "The general relativistic effects on neutrino-driven winds from young,hot neutron stars and the r-process nucleosynthesis."Astrophysical Journal. 533. 424-439 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] P.A.Mazzali: "A Spectroscopic Analysis of Energetic Types IC Hypernova SN 1997ef"Astrophysical Journal. 545. 407-419 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] T.Tsujimoto: "Probing the site for R-process nucleosynthesis with Abundances of Barium and Magnesium in …"Astrophysical Journal. 531. L33-L36 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] M.Chiba: "Kinematics of Metal-Poor Stars in the Galaxy III.Formation of the sellar Malo and thick Disk …"Astronomical Journal. 119. 2843-2865 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] J.Nakashima: "Period Measurement of AGB Stars in Outer Galactic Disk"Publ.Astron.Soc.Japan. 52. 275-294 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] T. K. Suzuki: "Evolution of Beryllium and Boron in the inhomogeneous early Galaxy"Astrophysical Journal, Letters. 522. 125-128 (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] A. Tokuhisa: "Meson synchrotron emission from central engines of Gamma-Ray Bursts with strong magnetic fields"Astrophysical Journal, Letters. 525. 117-120 (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] K. Otsuki: "General relativistic effects on neutrino-driven wind from young, hot neutron star and the γ-process nucleosynthesis"Astrophysical Journal. 535 (in press). (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] T. Kajino: "Impact of Few-Body reactions on explosive nucleosynthesis: The Big-Bang and Supernovae"Few-Body Systems, Supplement. (in press). (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] T. Kajino: "R-process nucleosynthesis in core-collapse supernova explosion"Nuclear Physics. (in press). (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] S. G. Ryan: "Abundances and evolution of Lithium in the Galaotic Halo and Disk"Astrophysical Journal. (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] T.Kajino: "Neutrinos and Big-Bang Nucleosynthesis." Nuclear Physics. A629. 538C-544C (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] N.Kunio: "High Disparsion Spectrograph(HDS)for Subaru Telescope." SPIE. 3355. 354-362 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] M.Chiba: "New limits on a cosmological constant from statistics of gravitational lensing." Astrophysical Journal. 510. 42-50 (1999)

    • Related Report
      1998 Annual Research Report
  • [Publications] Y.Takeda: "Nitrogen Abundances in Hyades F-Type Dwarfs." PASJ. 50. 509-517 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] K.Oyamatsu: "Can the equation of state of asymmetric nudear matter be studied using unstable nuclei?" Nudear Physics. A634. 3-14 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Y.Yoshii: "Age dating of a high-redshift QSO B1422+231 at Z=3.62 and its cosmological implications." Astrophysical Journal. 507. L113-L116 (1998)

    • Related Report
      1998 Annual Research Report

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Published: 1998-04-01   Modified: 2016-04-21  

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