Observational study of origin of the interstellar turbulence

• Project/Area Number: 23540277
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: Nagoya University (2013); National Astronomical Observatory of Japan (2011-2012)
• Principal Investigator: TACHIHARA Kengo 名古屋大学, 理学(系)研究科(研究院), 准教授 (70432565)
• Project Period (FY): 2011 – 2013
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2012: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2011: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 星間乱流 / 電波観測 / 星間磁場 / 電波天文学 / 星間物質 / 星形成

Research Abstract

We discovered small-scale structures of molecular clouds by high-resolution 12CO observations. The small-scale structures have much smaller velocity dispersions of the spectra compared to typical ones observed in the middle of molecular clouds. These imply that molecular clouds are not uniform entities, but consist of cold and dense small-scale structures in the thermal equilibrium, as suggested by the theoretical two-phase medium model and thermal instability of the warm neutral medium. These results gave clues about molecular cloud formation, one of the biggest issues of the interstellar physics. The follow-up observations of molecular and atomic gas with high angular resolution by ALMA and others are scheduled to solve the problems.

Research Products

• [Journal Article] Unusually bright 12CO(3-2) condensations in the tidally perturbed Small Magellanic Cloud "tail" (2014)
  • Author(s): Muller, E., Mizuno, N., Minamidani, T., Kawamura, A., Rosie Chen, C.-H., Indebetouw, R., Enokiya, R., Fukui, Y., Gordon, K., Hayakawa, T., Mizuno, Y., Murai, M., Okuda, T., Onishi, T., Tachihara, K., Takekoshi, T., Yamamoto, H., and Yoshiike, S.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 66 Issue: 1 Pages: 4-4
  • DOI: 10.1093/pasj/pst006
  • Peer Reviewed
• [Journal Article] A detailed study of non-thermal X-ray properties and interstellar gas toward the gamma-ray supernova remnant RX J1713.7-3946 (2014)
  • Author(s): Sano, H., Fukuda, T., Yoshiike, S., Sato, J., Horachi, H., Kuwahara, T., Torii, K., Hayakawa, T., Tanaka, T., Matsumoto, H., Inoue, T., Yamazaki, R., Inutsuka, S., Kawamura, A., Yamamoto, H., Okuda, T., Tachihara, K., Mizuno, N., Onishi, T., Mizuno, A., A
  • Journal Title: The Astrophysical Journal Volume: (in press)
  • Peer Reviewed
• [Journal Article] A detailed study of non-thermal X-ray properties and interstellar gas toward the gamma-ray supernova remnant RX J1713.7-3946 (2014)
  • Author(s): Sano, H.; Fukuda, T.; Yoshiike, S.; Sato, J.; Horachi, H.; Kuwahara, T.; Torii, K.; Hayakawa, T.; Tanaka, T.; Matsumoto, H.; Inoue, T.; Yamazaki, R.; Inutsuka, S.; Kawamura, A.; Yamamoto, H.; Okuda, T.; Tachihara, K.; Mizuno, N.; Onishi, T.; Mizuno, A.; Acero, F.; Fukui, Y.
  • Journal Title: The Astrophysical Journal Volume: 印刷中
  • Peer Reviewed
• [Journal Article] Non-thermal X-rays and interstellar gas toward the y-ray supernova remnant RX J1713.7-3946 : Evidence for X-ray enhancement around CO and HI clumps The Astrophysical Journal' (2013)
  • Author(s): Sano, H., et al.
  • Journal Title: The Astrophysical Journal Volume: 778 Issue: 1 Pages: 59-77
  • DOI: 10.1088/0004-637x/778/1/59
  • Peer Reviewed
• [Journal Article] Unveiling the gas-and-dust disk structure in HD 163296 using ALMA observations (2013)
  • Author(s): de Gregorio-Monsalvo, I., Ménard, F., Dent, W., Pinte, C., López, C., Klaassen, P., Hales, A., Cortés, P., Rawlings, M.G., Tachihara, K., Testi, L., Takahashi, S., Chapillon, E., Mathews, G., Juhasz, A., Akiyama, E., Higuchi, A.E., Saito, M., Nyman, L
  • Journal Title: Astronomy and Astrophysics Volume: 557 Pages: A133-A133
  • DOI: 10.1051/0004-6361/201321603
  • Peer Reviewed
• [Journal Article] Multi-site campaign for transit timing variations of WASP-12 b: possible detection of a long-period signal of planetary origin (2013)
  • Author(s): Maciejewski, G., Dimitrov, D., Seeliger, M., Tachihara, K. et al.
  • Journal Title: Astronomy & Astrophysics Volume: 551 Pages: A108-A108
  • DOI: 10.1051/0004-6361/201220739
  • Peer Reviewed
• [Journal Article] The Origin of the Interstellar Turbulence and Small Scale Structures of Molecular Clouds (2013)
  • Author(s): Tachihara, K.
  • Journal Title: ASP Conference series Volume: 476 Pages: 111-114
• [Journal Article] Giant Molecular Clouds and Star Formation in the Tidal Molecular Arm of NGC 4039 (2012)
  • Author(s): Espada, D., Komugi, S., Muller, E., Nakanishi, K., Saito, M., Tatematsu, K., Iguchi, S., Hasegawa, T., Mizuno, N. et al.
  • Journal Title: The Astrophysical Journal Letters Volume: Volume 760, Issue 2 Issue: 2 Pages: 25-29
  • DOI: 10.1088/2041-8205/760/2/l25
  • Peer Reviewed
• [Journal Article] Toward Understanding the Origin of Turbulence in Molecular Clouds: Small Scale Structures as Units of Dynamical Multi-Phase Interstellar Medium (2012)
  • Author(s): K. Tachihara, K. Saigo, Higuchi, A., Inoue, T., Inutsuka, S., et al.
  • Journal Title: The Astrophysical Journal Volume: 754 Issue: 2 Pages: 95-95
  • DOI: 10.1088/0004-637x/754/2/95
  • Peer Reviewed
• [Journal Article] The first ALMA view of IRAS 16293-2422. Direct detection of infall onto source B and high-resolution kinematics of source A (2012)
  • Author(s): Pineda, J.E., Maury, A.J., Fuller, G.A., Testi, L., García-Appadoo, D., Peck, A.B., Villard, E., Corder, S.A., van Kempen, T.A., Turner, J.L., Tachihara, K., & Dent, W
  • Journal Title: Astronomy and Astrophysics Volume: 544 Pages: L7-L7
  • DOI: 10.1051/0004-6361/201219589
  • Peer Reviewed
• [Journal Article] The Molecular Outflows in the rho Ophiuchi Main Cloud: Implications for Turbulence Generation (2012)
  • Author(s): Nakamura, F., Kamada, Y., Kamazaki, T., Kawabe, R., Kitamura, Y., Shimajiri, Y., Tsukagoshi, T., Tachihara, K., Akashi, T., Azegami, K., Ikeda, N., Kurono, Y., Li, Z.-Y., Miura, T., Nishi, R., & Umemoto, T., Erratum
  • Journal Title: The Astrophysical Journal Volume: 750 Issue: 2 Pages: 174-174
  • DOI: 10.1088/0004-637x/750/2/174
  • Peer Reviewed
• [Journal Article] Small Scale Structures as Units of Dynamical Multi-Phase Interstellar Medium (2012)
  • Author(s): Tachihara, K., Saigo, K., Higuchi, A., Inoue, T., & Inutsuka, S
  • Journal Title: American Astronomical Society Meeting Abstracts #219 Volume: 219
• [Journal Article] The Young Exoplanet Transit Initiative (YETI) (2011)
  • Author(s): Neuhäuser, R., Errmann, R., Berndt, A., Maciejewski, G., Takahashi, H., and 78 coauthors including Tachihara, K
  • Journal Title: Astronomische Nachrichten Volume: 332 Issue: 6 Pages: 547-547
  • DOI: 10.1002/asna.201111573
  • Peer Reviewed
• [Journal Article] The Young Exoplanet Transit Initiative (YETI) (2011)
  • Author(s): Neuhauser, R., Errmann, R., Berndt, Tachihara, K. et al.
  • Journal Title: AN Volume: 332 Pages: 547-561
  • Peer Reviewed
• [Journal Article] Transit timing variation and activity in the WASP-10 planetary system (2011)
  • Author(s): Maciejewski, G., Dimitrov, D., Neuhauser, R.,Tachihara, K., et al.
  • Journal Title: MNRAS Volume: 411 Pages: 1204-1212
  • Peer Reviewed
• [Journal Article] The Molecular Outflows in the ρ Ophiuchi Main Cloud: Implications for Turbulence Generation (2011)
  • Author(s): Nakamura, F., Kamada, Y., Kamazaki, T., Tachihara, K., et al.
  • Journal Title: ApJ Volume: 726 Pages: 46-60
  • Peer Reviewed
• [Presentation] Formation of molecular clouds and the origin of the interstellar turbulence (2014)
  • Author(s): Tachihara, K
  • Organizer: Birth and death of high-mass stars : Lesson on newly explored phases of the interstellar medium
  • Place of Presentation: Nagoya University
• [Presentation] Driving the interstellar turbulence and the initial conditions of molecular clouds (2014)
  • Author(s): Tachihara, K
  • Organizer: The Impact of Galactic Structure on Star Formation
  • Place of Presentation: Hokkaido University
• [Presentation] Planck 衛星のサーベイデータと星間ガスの比較解析 4 : HI 雲の㏿度構造 (2014)
  • Author(s): 立原研悟
  • Organizer: 日本天文学会春季年回
  • Place of Presentation: 国際基督教大学
• [Presentation] Formation of molecular clouds and the origin of the interstellar turbulence (2014)
  • Author(s): Kengo Tachihara
  • Organizer: Birth and death of high-mass stars: Lesson on newly explored phases of the interstellar medium
  • Place of Presentation: 名古屋大学
• [Presentation] Driving the interstellar turbulence and the initial conditions of molecular clouds (2014)
  • Author(s): Kengo Tachihara
  • Organizer: The Impact of Galactic Structure on Star Formation
  • Place of Presentation: 北海道大学
• [Presentation] Planck 衛星のサーベイデータと星間ガスの比較解析4:HI 雲の速度構造 (2014)
  • Author(s): 立原研悟、山本宏昭、早川貴敬、岡本竜治、服部桃、伊藤万記生、鳥居和史、桑原利尚、福井康雄
  • Organizer: 日本天文学会
  • Place of Presentation: 国際基督教大学
• [Presentation] Mopra mapping observations with multi-lines of dense cores in Lupus I (2014)
  • Author(s): 兼和紘, 立原研悟, 西合一矢, Tim van Kempen, 齋藤正雄, Paulo Cortes, Tracey Hill, Lewis Knee, 黒野泰隆, 高橋智子, 樋口あや, Lars Nyman
  • Organizer: 日本天文学会
  • Place of Presentation: 国際基督教大学
• [Presentation] TW Hya 周囲の原始惑星系円盤の ALMA Science Verification 観測 (2013)
  • Author(s): 立原研悟
  • Organizer: 日本天文学会秋季年回
  • Place of Presentation: 東北大学
  • Year and Date: 2013-09-11
• [Presentation] The NANTEN CO survey and SKA (2013)
  • Author(s): Tachihara, K
  • Organizer: SKA (Square Kilometer Array) Science Workshop in East Asia
  • Place of Presentation: Nagoya University
  • Year and Date: 2013-06-05
• [Presentation] Understanding of Gas and Dust Properties in the Interstellar Medium from the Planck All-sky Survey (2013)
  • Author(s): Tachihara, K
  • Organizer: The Life Cycle of Dust in the Universe : Observations
  • Place of Presentation: Theory, and Laboratory Experiments, Taipei
• [Presentation] The NANTEN CO survey and SKA (2013)
  • Author(s): Kengo Tachihara
  • Organizer: SKA (Square Kilometer Array) Science Workshop in East Asia
  • Place of Presentation: 名古屋大学
• [Presentation] TW Hya 周囲の原始惑星系円盤の ALMA Science Verification 観測 (2013)
  • Author(s): 立原研悟, 齋藤正雄, 西合一矢, 野村英子, C. Walsh, W.R.F. Dent, A. Hales, I. de Gregorio, T. van Kempen
  • Organizer: 日本天文学会
  • Place of Presentation: 東北大学
• [Presentation] Understanding of Gas and Dust Properties in the Interstellar Medium from the Planck All-sky Survey (2013)
  • Author(s): Kengo Tachihara, Hiroaki Yamamoto, Takahiro Hayakawa, Ryuji Okamoto, Momo Hattori, and Yasuo Fukui
  • Organizer: The Life Cycle of Dust in the Universe: Observations, Theory, and Laboratory Experiments
  • Place of Presentation: 台北
• [Presentation] Small Scale Structures as Units of Dynamical Multi-phase Interstellar Medium (2012)
  • Author(s): Tachihara, K
  • Organizer: American Astronomical Society meeting #219
  • Place of Presentation: Austin, TX, USA
  • Year and Date: 2012-01-12
• [Presentation] The Origin of the interstellar turbulence and small scale structures of molecular clouds (2012)
  • Author(s): Tachihara, K
  • Organizer: New Trends in Radio Astronomy in the ALMA Era
  • Place of Presentation: ザ・プリンス箱根
• [Presentation] Looking into the inner disk of TW Hya (2012)
  • Author(s): Tachihara, K
  • Organizer: The First Year of ALMA Science
  • Place of Presentation: Puerto Varas, Chile
• [Presentation] The Origin of the interstellar turbulence and small scale structures of molecular clouds (2012)
  • Author(s): Kengo Tachihara
  • Organizer: New Trends in Radio Astronomy in the ALMA Era
  • Place of Presentation: ザ・プリンス箱根（ 神奈川県）
• [Presentation] Small Scale Structures as Units of Dynamical Multi-Phase Interstellar Medium (2012)
  • Author(s): Tachihara, K., Saigo, K., Higuchi, A., Inoue, T.,Inutsuka, S.
  • Organizer: American Astronomical Society, AAS Meeting #219
  • Place of Presentation: Austin, TX, USA
• [Presentation] ALMA コミッショニング:CSV 活動全体の報告 (2011)
  • Author(s): 立原研悟 ほか JAO CSV チーム、ARC CSV サポートチーム
  • Organizer: 日本天文学会秋季年会
  • Place of Presentation: 鹿児島大学
• [Presentation] ALMA コミッショニング:アンテナグループ活動の報告 (2011)
  • Author(s): 立原研悟 ほか JAO CSV チーム、ARC CSV サポートチーム
  • Organizer: 日本天文学会秋季年会
  • Place of Presentation: 鹿児島大学
• [Book] The Origin of the Interstellar Turbulence and Small Scale Structures of Molecular Clouds (2013)
  • Author(s): Tachihara, K
  • Total Pages: 111
  • Publisher: ASP Conference Series
• [Book] Commissioning and Science Verification of ALMA (2011)
  • Author(s): Mauersberger, R., Villard, E., Peck, A. B., Asayama, S., Barkats, D., Calisse, P., Corder, S., Cortes, J., Cortes, P., de Gregorio, I., Dent, W. R. F., Fomalont, E., Fulla, D., Garcia-Appadoo, D., Gunawan, D., Hales, A., Hills, R. E., Kamazaki, T., Knee, L., Kneissl, R., Komugi, S., Leon, S., Lucas, R., Lundgren, A., Marconi, G., Matsushita, S., Planesas, P., Rawlings, M., Richards, A., Sawada, T., Simon, R., Tachihara, K., van Kempen, T., & Wiklind, T
  • Total Pages: 402
  • Publisher: IAU Symposium