Investigating Disk Galaxy Formation Through ALMA Observations of Merger Remnants

• Project/Area Number: 25800116
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: IONO Daisuke 国立天文台, チリ観測所, 准教授 (60425402)
• Research Collaborator: UEDA Junko 国立天文台, チリ観測所, 特任研究員 (60749935)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
• Keywords: 銀河形成 / 電波天文学 / 銀河衝突 / 分子ガス観測 / 銀河進化 / 銀河形成・進化 / 国際情報交換 / 銀河形成と進化

Outline of Final Research Achievements

The standard galaxy formation model predicts that galaxy collisions and mergers play an important role in the formation and evolution of disk galaxies. However, this process has not been proved observationally. Here we use the ALMA telescope to investigate whether galaxy collisions can lead to the formation of large disk galaxies.
We detected molecular gas emission from 30 galaxies out of the 37 galaxies that we have observed. Out of the 30 galaxies, 24 of them were found to posses rotating molecular gas disks. The size of the disks in a few of the galaxies were in fact comparable to the size of our own Milky Way galaxy. From this study, we suggest the possibility that galaxy collisions can indeed produce large rotating disk galaxies in the local universe.

Research Products

• [Journal Article] Cold Molecular Gas in Merger Remnants. I. Formation of Molecular Gas Disks (2014)
  • Author(s): Junko Ueda, Daisuke Iono, Min S. Yun, Alison F. Crocker, Desika Narayanan, Shinya Komugi, Daniel Espada, Bunyo Hatsukade, Hiroyuki Kaneko, Yuichi Matsuda, Yoichi Tamura, David J. Wilner, Ryohei Kawabe, Hsi-An Pan
  • Journal Title: The Astrophysical Journal Supplement Volume: 214 Issue: 1 Pages: 1-29
  • DOI: 10.1088/0067-0049/214/1/1
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Reformation of Cold Molecular Disks in Merger Remnants (2013)
  • Author(s): Ueda, J., Iono, D., Yun, M., Wilner, D., Narayanan, D., Hatsukade, B., Tamura, Y., Kaneko, H., Crocker, A., Espada, D., Kawabe, R.
  • Journal Title: ASP Conference Series Volume: 476 Pages: 61-64
• [Presentation] Investigating the evolution of merging galaxies via cold molecular gas (2014)
  • Author(s): 植田準子、伊王野大介
  • Organizer: Revolution in Astronomy with ALMA - the 3rd year -
  • Place of Presentation: Tokyo, Japan
  • Year and Date: 2014-12-08 – 2014-12-11
• [Presentation] 衝突末期段階の銀河における分子ガスの観測的研究 (2014)
  • Author(s): 植田準子、伊王野大介
  • Organizer: 日本天文学会 2014年秋季年会
  • Place of Presentation: 山形大学（山形県）
  • Year and Date: 2014-09-11 – 2014-09-13
• [Presentation] ALMA Science Highlights (2014)
  • Author(s): 伊王野大介
  • Organizer: International Union of Radio Science
  • Place of Presentation: Beijing, China
  • Year and Date: 2014-08-16 – 2014-08-23
  • Invited
• [Presentation] A Kiloparsec Scale Molecular Gas Disk in Late-stage Mergers (2014)
  • Author(s): 植田準子、伊王野大介
  • Organizer: Transformational Science in the ALMA Era: Multi-Wavelength Studies of Galaxy Evolution
  • Place of Presentation: Charlottesville, Virginia, USA
  • Year and Date: 2014-08-04 – 2014-08-07
• [Presentation] Cold Molecular Gas in Merger Remnants (2014)
  • Author(s): 植田準子、伊王野大介
  • Organizer: East Asia ALMA Science Workshop 2014
  • Place of Presentation: Jeju Island, Korea
  • Year and Date: 2014-07-14 – 2014-07-16
• [Presentation] Investigating the evolution of merger remnants from the formation of gas disks (2014)
  • Author(s): 植田準子、伊王野大介
  • Organizer: IAU Symposium 309: GALAXIES IN 3D ACROSS THE UNIVERSE
  • Place of Presentation: Vienna, Austria
  • Year and Date: 2014-07-07 – 2014-07-11
• [Presentation] Probing the evolution of merger remnants through formation of cold molecular gas disks (2014)
  • Author(s): 植田準子
  • Organizer: 3D2014: Gas and stars in galaxies: A multi-wavelength 3D perspective
  • Place of Presentation: ヨーロッパ南天天文台（ドイツ）
• [Presentation] The CO survey of Merger Remnants with ALMA (2014)
  • Author(s): 植田準子
  • Organizer: 日本天文学会 2014春季年会
  • Place of Presentation: 国際基督教大学（東京都）
• [Presentation] Synergy with ALMA beyond 2020 (2013)
  • Author(s): 伊王野大介
  • Organizer: GLAO Workshop
  • Place of Presentation: 北海道大学（北海道）
  • Invited
• [Presentation] Formation of Cold Molecular Gas Disk in Merger Remnants (2013)
  • Author(s): 植田準子
  • Organizer: 2013 Asia-Pacific Radio Science Conference
  • Place of Presentation: 台北、台湾（Howard International House）
• [Presentation] 分子ガス円盤の形成から探る衝突末期段階の衝突銀河の進化 (2013)
  • Author(s): 植田準子
  • Organizer: 日本天文学会 2013秋季年会
  • Place of Presentation: 東北大学（宮城県）
• [Remarks] Cold Molecular Gas in Merger Remnants
  • URL: http://alma-intweb.mtk.nao.ac.jp/~jueda/data/mr/index.html
• [Remarks] 銀河衝突で作られる巨大ガス円盤円盤銀河誕生の謎に電波で迫る
  • URL: http://alma.mtk.nao.ac.jp/j/news/pressrelease/201409177435.html
• [Remarks] Violent Origins of Pancake Galaxies Probed by ALMA
  • URL: http://www.almaobservatory.org/en/press-room/press-releases/751-violent-origins-of-pancake-galaxies-probed-by-alma