• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2007 Fiscal Year Final Research Report Summary

Numerical Astronomy using molecular and atomic line transfer calculations in the ALMA-era.

Research Project

Project/Area Number 16204012
Research Category

Grant-in-Aid for Scientific Research (A)

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

Principal Investigator

MIYAMA Shoken  National Astronomical Observatory of Japan, Director (00166191)

Co-Investigator(Kenkyū-buntansha) TOMISAKA Kohji  National Astronomical Observatory of Japan, Theoretical Astrophysics Division, Professor (70183879)
WADA Keiichi  National Astronomical Observatory of Japan, Theoretical Astrophysics Division, Associate Professor (30261358)
OMUKAI Kazuyuki  National Astronomical Observatory of Japan, Theoretical Astrophysics Division, Associate Professor (70390622)
KOHNO Kotaro  The University of Tokyo, Graduate School of Department of Science, Associate Professor (80321587)
TOMOHARU Oka  The University of Tokyo, Graduate School of Department of Science, Assistant Professor (10291056)
Project Period (FY) 2004 – 2007
KeywordsNumerical Simulation / Radiative Transfer / Interstellar matter
Research Abstract

We explore millimeter line diagnostics of an obscuring molecular torus modeled by a hydrodynamic simulation with three-dimensional non-local thermodynamic equilibrium radiative transfer calculations. Based on the results of a high-resolution hydrodynamic simulation of the molecular torus around an active galactic nucleus, we calculate the intensities of the HCN and HCO+ rotational lines as two representative high-density tracers. Three-dimensional radiative transfer calculations shed light on a complicated excitation state in the inhomogeneous torus, even though a spatially uniform chemical structure is assumed. We find that similar transition coefficients for the HCN and HCO+ rotational lines lead to a natural concordance of the level population distributions of these molecules and a line ratio RHCN/HC0+<〜1 for the same molecular abundance value over 2 orders of magnitude. Our results suggest that HCN must be much more abundant than HCO+ (yHCN>〜10yHCO+) in order to obtain the high ratio (RHCN/HCO+-2) observed in some nearby galaxies. There is a remarkable dispersion in the relation between integrated intensity and column density, indicative of possible shortcomings of the HCN (1-0) and HCO+ (1-0) lines as high-density tracers. The internal structures of inhomogeneous molecular tori down to subparsec scales in external galaxies will be revealed by the forthcoming Atacama Large Millimeter/submillimeter Array. Three-dimensional radiative transfer calculations of molecular lines with a high-resolution hydrodynamic simulation prove to be a powerful tool to provide a physical basis for molecular-line diagnostics of the central regions of external galaxies.

  • Research Products

    (44 results)

All 2009 2008 2007

All Journal Article (23 results) (of which Peer Reviewed: 10 results) Presentation (20 results) Book (1 results)

  • [Journal Article] Instabilities of Spiral Shocks.II.A Quasi-Steady State in the Multiphase Inhomogeneous ISM2008

    • Author(s)
      和田 桂一
    • Journal Title

      The Astrophysical Journal 675

      Pages: 188-193

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Three Dimensional Molecular Line Transfer Study of Extragalactic ISM:AGN/Starburst Connection2008

    • Author(s)
      山田 雅子
    • Journal Title

      Proceedings of "Far-Infrared and Submillimeter Emission of the Interstellar Medium", EAS Publication Series, Bad Honnef, November 2007, Eds.C.Kramer, S.Aalto, R.Simon

    • Description
      「研究成果報告書概要(和文)」より
  • [Journal Article] Evolution of First Cores and Formation of Stellar Cores in Rotating Molecular Cloud Cores2008

    • Author(s)
      Saigo, K., Tomisaka, K., Matsumoto, T.
    • Journal Title

      The Astrophysical Journal 674

      Pages: 997-1014

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Formation Scenario for Wide and Close Binary Systems2008

    • Author(s)
      Machida M.N., Tomisaka K., Matsumoto T., Inutsuka S.-i.
    • Journal Title

      The Astrophysical Journal (印刷中)

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] How was the mushroom-shaped GW 123.4-1.5 formed in the Galactic disk2008

    • Author(s)
      Baek C.H., Kudoh T., Tomisaka K.
    • Journal Title

      The Astrophysical Journal (印刷中)

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Instabilities of Spiral Shocks. II. A Quasi-Steady State in the Multiphase Inhomogeneous ISM2008

    • Author(s)
      Wada, K.
    • Journal Title

      The Astrophysical Journal 675

      Pages: 188-193

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Evolution of First Cores and Formation of Stellar Cores in Rotating Molecular Cloud Cores2008

    • Author(s)
      Saigo, K., Tomisaka, K.
    • Journal Title

      The Astrophysical Journal 674

      Pages: 997-2014

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Formation Scenario for Wide and Close Binary Systems2008

    • Author(s)
      Machida M. N., Tomisaka K., Matsumoto T., Inutsuka S-i.
    • Journal Title

      The Astrophysical Journal (in press)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] How was the mushroom-shaped GW 123.4‥1.5 formed in the Galactic disk?2008

    • Author(s)
      Baek C. H., Kudoh T., Tomisaka K.
    • Journal Title

      The Astrophysical Journal (in press)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Mapping the Galaxy and Nearby Galaxies Springer, New York2008

    • Author(s)
      Wada, K., Combes, F.
    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Synthetic Observations of Carbon Lines of Turbulent Flows in the Diffuse Multiphase Interstellar Medium2007

    • Author(s)
      山田 雅子, 小山 洋, 大向 一行, 犬塚 修一郎
    • Journal Title

      The Astrophysical Journal 657

      Pages: 849-859

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] HCN to HCO^+ Millimeter Line Diagnostics of AGN Molecular Tori.I.Radiative Transfer Modelling2007

    • Author(s)
      山田 雅子, 和田 桂一, 富阪 幸治
    • Journal Title

      The Astrophysical Journal 671

      Pages: 73-84

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Origin of Warm High-Velocity Dense Gas in Ultraluminous Infrared Galaxies2007

    • Author(s)
      和田 桂一
    • Journal Title

      Publications of Astronomical Society of Japan 59

      Pages: 711-716

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Observational Characteristics of the First Protostellar Cores2007

    • Author(s)
      大向 一行
    • Journal Title

      Publications of Astronomical Society of Japan 59

      Pages: 589-606

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Formation of Massive Primordial Stars in a Reionized Gas2007

    • Author(s)
      吉田 直紀, 大向 一行, Hernquist, L.
    • Journal Title

      The Astrophysical Journal 667

      Pages: L117-L120

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Current Advances in the Methodology and Computational Simulation of the Formation of Low-Mass Stars2007

    • Author(s)
      Klein R.I., Inutsuka S.-I., Padoan P., Tomisaka K.
    • Journal Title

      Protostars and Planets

      Pages: 99-116

    • Description
      「研究成果報告書概要(和文)」より
    • Peer Reviewed
  • [Journal Article] Synthetic Observations of Carbon Lines of Turbulent Flows in the Diffuse Multiphase Interstellar Medium2007

    • Author(s)
      Yamada, M., et. al.
    • Journal Title

      The Astrophysical Journal 657

      Pages: 849-859

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] HCN to HCO+ Millimeter Line Diagnostics of AGN Molecular Tori. I. Radiative Transfer Modelling2007

    • Author(s)
      Yamada, M., et. al.
    • Journal Title

      The Astrophysical Journal 671

      Pages: 73-84

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Origin of Warm High-Velocity Dense Gas in Ultraluminous Infrared Galaxies2007

    • Author(s)
      Wada, K.
    • Journal Title

      Publications of Astronomical Society of Japan 59

      Pages: 711-716

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Observational Characteristics of the First Protostellar Cores2007

    • Author(s)
      Omukai, K.
    • Journal Title

      Publications of Astronomical Society of Japan 59

      Pages: 589-606

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Formation of Massive Primordial Stars in a Reionized Gas2007

    • Author(s)
      Yoshida, N., Omukai, K.
    • Journal Title

      The Astrophysical Journal 667

      Pages: L117-L120

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Three Dimensional Molecular Line Transfer Study of Extragalactic ISM : AGN/Starburst Connection2007

    • Author(s)
      Yamada, M.
    • Journal Title

      Proceedings of Far-Infrared and Submillimeter Emission of the Interstellar Medium, EAS Publication Series, Bad Honnef(Eds. C. Kramer, S. Aalto, R. Simon)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Journal Article] Current Advances in the Methodology and Computational Simulation of the For ination Low-Mass Stars2007

    • Author(s)
      Klein R. I., Inutsuka S.-I., Padoan P., Tomisaka K.
    • Journal Title

      Protostars and Planets

      Pages: 99-116

    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Radiative Transfer and ISM2009

    • Author(s)
      Yamada, M.
    • Organizer
      ICC, Durham Radiative Transfer Workshop
    • Place of Presentation
      Durham, UK
    • Year and Date
      2009-09-03
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Modeling ISM, Star Formation and Feedback in 3-D Galactic Disks2008

    • Author(s)
      Wada, K.
    • Organizer
      Gas Accretion and Star Formation in Galaxies
    • Place of Presentation
      Garching, Germany
    • Year and Date
      2008-09-14
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] 非一様分子ガス中の高密度トレーサー輝線比について2008

    • Author(s)
      山田 雅子, 富阪 幸治
    • Organizer
      日本天文学会2008年春季年会
    • Place of Presentation
      国立オリンピック記念青少年総合センター
    • Year and Date
      2008-03-24
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] ON the Line Ratio of high density tracers in inhomogeneous molecular gases2008

    • Author(s)
      Yamada, M.
    • Organizer
      Annual meeting of ASJ
    • Place of Presentation
      Tokyo
    • Year and Date
      2008-03-24
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Coevolution of AGNs and Nuclear Starbursts2008

    • Author(s)
      和田 桂一
    • Organizer
      Nuclear Star Clusters accross the Hubble Sequence
    • Place of Presentation
      MPIA,Heidelberg,ドイツ
    • Year and Date
      2008-02-27
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Coevolution of AGNs and Nuclear Starbursts2008

    • Author(s)
      Wada, K.
    • Organizer
      Nuclear Star Clusters accross the Hubble Sequence
    • Year and Date
      2008-02-27
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Three Dimensional Molecular Line Transfer Study of Extragalactic ISM:AGN/Starburst Connection2007

    • Author(s)
      山田 雅子
    • Organizer
      FIR Workshop 2007:"Far-Infrared and Submillimeter Emission of the Interstellar Medium:Models meet Extragalactic Galactic Observations"
    • Place of Presentation
      Phyzikzentrum,Bad Honnef(Germany)
    • Year and Date
      2007-11-06
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Three Dimensional Molecular Line Transfer Study of Extragalactic ISM : AGN/Starburst Connection2007

    • Author(s)
      Yamada, M.
    • Organizer
      FIR Workshop 2007 : Far-Infrared and Sub millimeter Emission of the Interstellar Medium : Models meet Extragalactic Galactic Observations
    • Place of Presentation
      Phyzikzentrum, Bad Honnef, Germany
    • Year and Date
      2007-11-06
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Modeling 3-D ISM in Galactic Disks using Grid and Particle-Based Simulations2007

    • Author(s)
      和田 桂一
    • Organizer
      Next generation of computational models of baryonic physics in galaxy formation
    • Place of Presentation
      ETH,Zurich,スイス
    • Year and Date
      2007-09-20
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Modeling 3-D ISM in Galactic Disks using Grid and Particle-Based Simulations2007

    • Author(s)
      Wada, K.
    • Organizer
      Next generation of computational models of baryonic physics in galaxy formation
    • Place of Presentation
      Zurich, Switzerland
    • Year and Date
      2007-09-20
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Modeling ISM,Star Formation and Feedback in 3-D Galactic Disks2007

    • Author(s)
      和田 桂一
    • Organizer
      Gas Accretion and Star Formation in Galaxies
    • Place of Presentation
      MPA,Garching,ドイツ
    • Year and Date
      2007-09-14
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] 3D Molecular Transfer Study of Extragalactic ISM towards ALMA2007

    • Author(s)
      山田 雅子
    • Organizer
      Durham Radiative Transfer Workshop
    • Place of Presentation
      ICC,Durham University(UK)
    • Year and Date
      2007-09-04
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] 3D Molecular Transfer Study of Extragalactic ISM towards ALMA2007

    • Author(s)
      Yamada, M.
    • Organizer
      ICC, Durham Radiative Transfer Workshop
    • Year and Date
      2007-09-04
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Radiative Transfer and ISM(review talk)2007

    • Author(s)
      山田 雅子
    • Organizer
      Durham Radiative Transfer Workshop
    • Place of Presentation
      ICC,Durham University(UK)
    • Year and Date
      2007-09-03
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Radiative Transfer Approach to Millimeter and Submillimeter Molecular Line Diagnostics of AGN Molecular Torus2007

    • Author(s)
      山田 雅子
    • Organizer
      SPICA Science Workshop
    • Place of Presentation
      JAXA
    • Year and Date
      2007-05-24
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Radiative Transfer Approach to Millimeter and Submillimeter Molecular Line Diagnostics of AGN Molecular Torus2007

    • Author(s)
      Yamada, M.
    • Organizer
      SPICA Science Workshop
    • Place of Presentation
      JAXA, Japan
    • Year and Date
      2007-05-24
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Structure of the ISM in Galactic Disks2007

    • Author(s)
      和田 桂一
    • Organizer
      ALMA Japan-Taiwan Scientic Meeting
    • Place of Presentation
      Chungli,Taiwan
    • Year and Date
      2007-04-14
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Structure of the ISM in Galactic Disks2007

    • Author(s)
      Wada, K.
    • Organizer
      ALMA Japan-Taiwan Scientic Meeting
    • Place of Presentation
      Chungli, Taiwan
    • Year and Date
      2007-04-14
    • Description
      「研究成果報告書概要(欧文)」より
  • [Presentation] Millimeter and Submillimeter Line Diagnostics of AGN Molecular Torus:3D Radiative Transfer Approach2007

    • Author(s)
      山田 雅子
    • Organizer
      3rd ALMA-JT Science Wrokshop
    • Place of Presentation
      台湾中央大学
    • Year and Date
      2007-04-13
    • Description
      「研究成果報告書概要(和文)」より
  • [Presentation] Millimeter and Submillimeter Line Diagnostics of AGN Molecular Torus : 3D Radiative Transfer Approach2007

    • Author(s)
      Yamada, M.
    • Organizer
      ALMA Japan-Taiwan Scientic Meeting
    • Place of Presentation
      Chungli, Taiwan
    • Year and Date
      2007-04-13
    • Description
      「研究成果報告書概要(欧文)」より
  • [Book] Mapping the Galaxy and Nearby Galaxies2008

    • Author(s)
      和田 桂一, F.Combes
    • Total Pages
      392
    • Publisher
      Springer
    • Description
      「研究成果報告書概要(和文)」より

URL: 

Published: 2010-02-04  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi