高密度分子ガストレーサーを用いた、衝突銀河における星形成・ＳＭＢＨ活動の研究

• Project/Area Number: 14J08134
• Research Category: Grant-in-Aid for JSPS Fellows
• Allocation Type: Single-year Grants
• Section: 国内
• Research Field: Astronomy
• Research Institution: The University of Tokyo
• Principal Investigator: 斉藤 俊貴 東京大学, 理学系研究科, 特別研究員(DC1)
• Project Period (FY): 2014-04-25 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥2,700,000 (Direct Cost: ¥2,700,000); Fiscal Year 2016: ¥800,000 (Direct Cost: ¥800,000); Fiscal Year 2015: ¥800,000 (Direct Cost: ¥800,000); Fiscal Year 2014: ¥1,100,000 (Direct Cost: ¥1,100,000)
• Keywords: 銀河形成 / 銀河進化 / 銀河衝突 / ALMA / 電波天文学 / 衝突銀河

Outline of Annual Research Achievements

本年度の研究実施計画(年次計画)に従い、申請者を筆頭研究者とする研究グループが前年度までにALMA望遠鏡を用いて取得した複数の衝突銀河(VV114, NGC1614)のデータの解析、論文化をおこなった。以下に具体的な成果を示す。

VV114では、超高帯域かつ高空間分解能観測等の詳細観測を実行した。これらのデータの解析から、星形成の材料となる分子ガスの物理的、化学的な診断を行い、爆発的星形成領域、活動銀河中心核、オーバーラップ領域(衝突している銀河同士の衝突面)の3つの領域の物理状態、分子組成の違いについて調べた。結果として、衝突による衝撃波が星形成の引き金となった観測的な証拠(オーバーラップ領域におけるメタノール分子の過剰生成)を得た。メタノール分子輝線を使った診断方法は今後、衝突銀河の物理化学状態を診断する新たな手法として期待できる。
NGC1614では複数の一酸化分子ガス輝線や電波連続波を高分解能かつ高感度で調べ、星形成関係を調べた。これは、現存する複数の一酸化分子ガス輝線観測の中で最も高分解能のものである。

これらの成果は今年度中に2本の査読論文として発表し。それに加え１本の論文を投稿中、１本の解説を学術雑誌に投稿済みである。さらに、特別研究員採用中に出版した論文計4本の結果を国際研究会で招待講演により発表した。また主著論文とは別に、共著論文として4本が本年度中に受理された。博士論文はこれらの結果を中心にまとめ、博士号を取得した。

Research Progress Status

28年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

28年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] チャルマース工科大学(スウェーデン)
• [Int'l Joint Research] マックスプランク天文学研究所/ハイデルベルク大学(ドイツ)
• [Int'l Joint Research] マサチューセッツ大学/カリフォルニア工科大学(米国)
• [Int'l Joint Research] 合同アルマ観測所(チリ)
• [Int'l Joint Research] マサチューセッツ大学(米国)
• [Int'l Joint Research] 合同アルマ観測所(チリ)
• [Journal Article] Merger-induced Shocks in the Nearby LIRG VV 114 through Methanol Observations with ALMA (2017)
  • Author(s): Saito T., Iono D., Espada D., Nakanishi K., Ueda J., Sugai H., Takano S., Yun M. S., Imanishi M., Ohashi S., Lee M., Hagiwara Y., Motohara K., Kawabe R.
  • Journal Title: The Astrophysical Journal Volume: 834 Issue: 1 Pages: 6-6
  • DOI: 10.3847/1538-4357/834/1/6
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Spatially resolved CO SLED of the Luminous Merger Remnant NGC 1614 with ALMA (2017)
  • Author(s): Saito T., Iono D., Xu C. K., Sliwa K., Ueda J., Espada D., Kaneko H., König S., Nakanishi K., Lee M., Yun M. S., Aalto S., Hibbard J. E., Yamashita T., Motohara K., Kawabe R.
  • Journal Title: The Astrophysical Journal Volume: 835 Issue: 2 Pages: 174-174
  • DOI: 10.3847/1538-4357/835/2/174
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] ALMA observations of the dense and shocked gas in the nuclear region of NGC 4038 (Antennae galaxies) (2017)
  • Author(s): Ueda, Junko; Watanabe, Yoshimasa; Iono, Daisuke; Wilner, David J.; Fazio, Giovanni G.; Ohashi, Satoshi; Kawabe, Ryohei; Saito, Toshiki; Komugi, Shinya
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 69 Issue: 1 Pages: 6-6
  • DOI: 10.1093/pasj/psw110
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Luminous Infrared Galaxies with the Submillimeter Array V: Molecular Gas in Intermediate to Late-stage Mergers (2017)
  • Author(s): Sliwa, Kazimierz; Wilson, Christine D.; Matsushita, Satoki; Peck, Alison B.; Petitpas, Glen R.; Saito, Toshiki; Yun, Min
  • Journal Title: The Astrophysical Journal Volume: 印刷中
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Investigating the relation between CO (3-2) and far-infrared luminosities for nearby merging galaxies using ASTE (2016)
  • Author(s): Tomonari Michiyama, Daisuke Iono, Kouichiro Nakanishi, Junko Ueda, Toshiki Saito, Misaki Ando, Hiroyuki Kaneko, Takuji Yamashita, Yuichi Matsuda, Bunyo Hatsukade, Kenichi Kikuchi, Shinya Komugi, Takayuki Muto
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 68 Issue: 6
  • DOI: 10.1093/pasj/psw087
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Clumpy and Extended Starbursts in the Brightest Unlensed Submillimeter Galaxies (2016)
  • Author(s): Iono, Daisuke; Yun, Min S.; Aretxaga, Itziar; Hatsukade, Bunyo; Hughes, David; Ikarashi, Soh; Izumi, Takuma; Kawabe, Ryohei; Kohno, Kotaro; Lee, Minju; Matsuda, Yuichi; Nakanishi, Kouichiro; Saito, Toshiki; Tamura, Yoichi; Ueda, Junko; Umehata, Hideki; Wilson, Grant; Michiyama, Tomonari; Ando, Misaki
  • Journal Title: ApJ Letters Volume: 829 Issue: 1 Pages: L10-L10
  • DOI: 10.3847/2041-8205/829/1/l10
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Spatially resolved radio-to-far-infrared SED of the luminous merger remnant NGC 1614 with ALMA and VLA (2016)
  • Author(s): Saito, Toshiki; Iono, Daisuke; Xu, Cong K.; Ueda, Junko; Nakanishi, Kouichiro; Yun, Min S.; Kaneko, Hiroyuki; Yamashita, Takuji; Lee, Minju; Espada, Daniel; Motohara, Kentaro; Kawabe, Ryohei
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 68 Issue: 2 Pages: 20-30
  • DOI: 10.1093/pasj/psv136
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] ALMA Multi-line Observations of the IR-bright Merger VV 114 (2015)
  • Author(s): Saito, Toshiki; Iono, Daisuke; Yun, Min S.; Ueda, Junko; Nakanishi, Kouichiro; Sugai, Hajime; Espada, Daniel; Imanishi, Masatoshi; Motohara, Kentaro; Hagiwara, Yosiaki; Tateuchi, Ken; Lee, Minju; Kawabe, Ryohei
  • Journal Title: The Astrophysical Journal Volume: 803 Issue: 2 Pages: 60-93
  • DOI: 10.1088/0004-637x/803/2/60
  • Peer Reviewed / Open Access
• [Journal Article] Detection of Molecular Gas in Void Galaxies : Implications for Star Formation in Isolated Environments (2015)
  • Author(s): Das, M.; Saito, T.; Iono, D.; Honey, M.; Ramya, S.
  • Journal Title: The Astrophysical Journal Volume: 815 Issue: 1 Pages: 40-48
  • DOI: 10.1088/0004-637x/815/1/40
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Investigating AGN/Starburst activities through ALMA multi-line observations in the mid-stage IR-bright merger VV 114 (2015)
  • Author(s): Saito, Toshiki; Iono, Daisuke; Yun, Min S.; Ueda, Junko; Espada, Daniel; Hagiwara, Yoshiaki; Imanishi, Masatoshi; Motohara, Kentaro; Nakanishi, Kouichiro; Sugai, Hajime; Tateuchi, Ken; Lee, Minju; Kawabe, Ryohei
  • Journal Title: Proceedings of the International Astronomical Union Volume: 309 Issue: S309 Pages: 196-199
  • DOI: 10.1017/s174392131400965x
  • Open Access / Int'l Joint Research
• [Presentation] Shock-induced Starbursts in the Nearby LIRG VV 114 with ALMA (2017)
  • Author(s): 斉藤俊貴
  • Organizer: 日本天文学会2017年春季年会
  • Place of Presentation: 九州大学伊都キャンパス (福岡県福岡市)
  • Year and Date: 2017-03-15
• [Presentation] Revealing Physical, Chemical, and Morphological Structures of Nearby Luminous Infrared Galaxies (2017)
  • Author(s): Toshiki Saito
  • Organizer: East-Asian ALMA Science Workshop 2016-Taiwan
  • Place of Presentation: Hsinchu (Taiwan)
  • Year and Date: 2017-03-10
  • Int'l Joint Research / Invited
• [Presentation] Revealing Physical, Chemical, and Morphological Structures of the Luminous Infrared Galaxy VV 114 with ALMA (2016)
  • Author(s): Toshiki Saito
  • Organizer: Half a Decade of ALMA: Cosmic Downs Transformed
  • Place of Presentation: Indian Wells (USA)
  • Year and Date: 2016-09-20
  • Int'l Joint Research
• [Presentation] Spatially-resolved SED and CO SLED of the merging LIRG NGC 1614 (2016)
  • Author(s): 斉藤俊貴
  • Organizer: 日本天文学会2016年秋季年会
  • Place of Presentation: 愛媛大学城北キャンパス (愛媛県松山市)
  • Year and Date: 2016-09-14
• [Presentation] 3 mm and 2 mm Spectral Scan for the Nearby IR-bright Merging Galaxy VV 114 (2015)
  • Author(s): Toshiki Saito
  • Organizer: East Asian ALMA Science Workshop 2015
  • Place of Presentation: I-site Namba (Osaka, Japan)
  • Year and Date: 2015-12-08
  • Int'l Joint Research
• [Presentation] Unexpected Discovery of z ~ 2.5 Dusty Star-forming Galaxies with ALMA 54 GHz-wide Spectral Scan (2015)
  • Author(s): Toshiki Saito
  • Organizer: East Asian ALMA Science Workshop 2015
  • Place of Presentation: I-site Namba (Osaka, Japan)
  • Year and Date: 2015-12-08
  • Int'l Joint Research
• [Presentation] Diffuse and dense Gas in nearby luminous merging galaxies (2014)
  • Author(s): Toshiki Saito
  • Organizer: Revolution in Astronomy with ALMA -The 3rd Year-
  • Place of Presentation: Tokyo International Forum (Tokyo, Japan)
  • Year and Date: 2014-12-10
  • Int'l Joint Research
• [Presentation] Spatially Resolved Molecular Gas in AGN/Starburst/Overlap of the Luminous Merging Galaxy VV 114 with ALMA (2014)
  • Author(s): Toshiki Saito
  • Organizer: East Asia ALMA Science Workshop 2014
  • Place of Presentation: Phoenix island (Jeju, Korea)
  • Year and Date: 2014-07-15
  • Int'l Joint Research
• [Presentation] Investigating AGN/Starburst activities through ALMA Multi-line observations in the mid-stage IR-bright merger VV 114 (2014)
  • Author(s): Toshiki Saito
  • Organizer: IAU Symposium 309
  • Place of Presentation: Hawaii Convention Center (Honolulu, U.S.)
  • Year and Date: 2014-07-09
  • Int'l Joint Research