Research for the Cosmic Web in the early Universe

• Project/Area Number: 17H04831
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: Matsuda Yuichi 国立天文台, アルマプロジェクト, 助教 (20647268)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥23,790,000 (Direct Cost: ¥18,300,000、Indirect Cost: ¥5,490,000); Fiscal Year 2020: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2019: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000); Fiscal Year 2018: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000); Fiscal Year 2017: ¥14,690,000 (Direct Cost: ¥11,300,000、Indirect Cost: ¥3,390,000)
• Keywords: 銀河形成 / 宇宙網 / 観測天文学 / 銀河間ガス / すばる望遠鏡 / 宇宙物理 / 光学赤外線天文学 / 電波天文学

Outline of Final Research Achievements

We made a special narrow-band filter NB0497 for Subaru/HSC. Based on this filter, we are undertaking Lyman-alpha observations of the cosmic web in and around the well-studied SSA22 protocluster at redshit z=3.09 as a Subaru Intensive program. Our program is scheduled from 2021 to 2023 and the total observation time is 98 hours. We also obtained CFHT U-band time as an international joint research project. We analyzed old Subaru/Keck Lyman-alpha imaging data and found a hint of Mpc-scale filamentary structure connecting massive galaxies toward this protocluster. We proceeded ALMA and VLT/MUSE observations to confirm this structure and published the first result on Science Journal.

Academic Significance and Societal Importance of the Research Achievements

初期宇宙では銀河やブラックホールなどのもととなる水素ガスは宇宙網と呼ばれる網の目構造のパイプの中を通って、網の目の結び目に向かって流れ込んでいると考えられており、その性質を調べることが天体形成の謎を解明するための鍵となる。我々は、すばる望遠鏡、アルマ望遠鏡を含む世界中の巨大望遠鏡群を使って、世界で初めて、形成期の銀河を繋ぐガスネットワーク構造の観測に成功した。さらに、すばる望遠鏡の超広視野カメラ用に製作した特注光学フィルターを使って、より広範囲でガスネットワークを観測して、銀河が形成される時代の宇宙における宇宙網の地図作成を進める。

Research Products

• [Int'l Joint Research] Dalhousie University(カナダ)
• [Int'l Joint Research] Durham University(英国)
• [Int'l Joint Research] Caltech/Princeton University(米国)
• [Int'l Joint Research] ダーラム大学(英国)
• [Int'l Joint Research] カリフォルニア工科大学(米国)
• [Int'l Joint Research] Durham University(英国)
• [Int'l Joint Research] Caltech(米国)
• [Journal Article] FIR-luminous [C II] Emitters in the ALMA-SCUBA-2 COSMOS Survey (AS2COSMOS): The Nature of Submillimeter Galaxies in a 10 Comoving Megaparsec-scale Structure at z~4.6 (2021)
  • Author(s): Mitsuhashi, Matsuda, Smail, Hayatsu, Simpson, Swinbank, Umehata, Dudzeviciute, Birkin, Ikarashi, Chen, Tadaki, Yajima, Harikane, Inami, Chapman, Hatsukade, Iono, Bunker, Ao, Saito, Ueda, and Sakamoto
  • Journal Title: The Astrophysical Journal Volume: 907 Issue: 2 Pages: 122-122
  • DOI: 10.3847/1538-4357/abcc72
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Three-dimensional Distribution Map of H i Gas and Galaxies around an Enormous Lyα Nebula and Three QSOs at z = 2.3 Revealed by the H i Tomographic Mapping Technique (2020)
  • Author(s): Mukae S., Ouchi M., Cai Z., Lee K-G., and 20 coauthors including Suzuki, Nao
  • Journal Title: The Astrophysical Journal Volume: 896 Issue: 1 Pages: 45-45
  • DOI: 10.3847/1538-4357/ab8db7
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Large Population of ALMA Galaxies at z > 6 with Very High [O iii] 88 μm to [C ii] 158 μm Flux Ratios: Evidence of Extremely High Ionization Parameter or PDR Deficit? (2020)
  • Author(s): Harikane Yuichi、Ouchi Masami、Inoue Akio K.、Matsuoka Yoshiki、Tamura Yoichi、Bakx Tom、Fujimoto Seiji、Moriwaki Kana、Ono Yoshiaki、Nagao Tohru、Tadaki Ken-ichi、Kojima Takashi、Shibuya Takatoshi、Egami Eiichi、Ferrara Andrea、Gallerani Simona、Hashimoto Takuya、Kohno Kotaro、Matsuda Yuichi、Matsuo Hiroshi、et al.
  • Journal Title: The Astrophysical Journal Volume: 896 Issue: 2 Pages: 93-93
  • DOI: 10.3847/1538-4357/ab94bd
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] An ALMA survey of the brightest sub-millimetre sources in the SCUBA-2?COSMOS field (2020)
  • Author(s): Simpson J M et al.
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 495 Issue: 3 Pages: 3409-3430
  • DOI: 10.1093/mnras/staa1345
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] An ALMA/NOEMA survey of the molecular gas properties of high-redshift star-forming galaxies (2020)
  • Author(s): Birkin Jack E et al.
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 501 Issue: 3 Pages: 3926-3950
  • DOI: 10.1093/mnras/staa3862
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Detection of the Far-infrared [O iii] and Dust Emission in a Galaxy at Redshift 8.312: Early Metal Enrichment in the Heart of the Reionization Era (2019)
  • Author(s): Tamura Yoichi、Mawatari Ken、Hashimoto Takuya、Inoue Akio K.、Zackrisson Erik、Christensen Lise、Binggeli Christian、Matsuda Yuichi、Matsuo Hiroshi、Takeuchi Tsutomu T.、Asano Ryosuke S.、Sunaga Kaho、Shimizu Ikkoh、Okamoto Takashi、Yoshida Naoki、et al.
  • Journal Title: The Astrophysical Journal Volume: 874 Issue: 1 Pages: 27-27
  • DOI: 10.3847/1538-4357/ab0374
  • NAID: 120006650166
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The distribution and physical properties of high-redshift [O?iii] emitters in a cosmological hydrodynamics simulation (2018)
  • Author(s): Moriwaki Kana、Yoshida Naoki、Shimizu Ikkoh、Harikane Yuichi、Matsuda Yuichi、Matsuo Hiroshi、Hashimoto Takuya、Inoue Akio K、Tamura Yoichi、Nagao Tohru
  • Journal Title: Monthly Notices of the Royal Astronomical Society: Letters Volume: 481 Issue: 1 Pages: L84-L88
  • DOI: 10.1093/mnrasl/sly167
  • Peer Reviewed
• [Journal Article] A high dust emissivity index β for a CO-faint galaxy in a filamentary Lyα nebula at z = 3.1 (2018)
  • Author(s): Kato Yuta、Matsuda Yuichi、Iono Daisuke、Hatsukade Bunyo、Umehata Hideki、Kohno Kotaro、Alexander David M、Ao Yiping、Chapman Scott C、Hayes Matthew、Kubo Mariko、Lehmer Bret D、Malkan Matthew A、Michiyama Tomonari、Nagao Tohru、Saito Tomoki、Tanaka Ichi、Taniguchi Yoshiaki
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: 5 Pages: 6-11
  • DOI: 10.1093/pasj/psy087
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The onset of star formation 250 million years after the Big Bang (2018)
  • Author(s): Hashimoto Takuya、Laporte Nicolas、Mawatari Ken、Umehata Hideki et al
  • Journal Title: Nature Volume: 557 Issue: 7705 Pages: 392-395
  • DOI: 10.1038/s41586-018-0117-z
  • Peer Reviewed / Int'l Joint Research
• [Presentation] 赤方偏移 4.6 の大規模構造におけるサブミリ波銀河の性質 (2021)
  • Author(s): 三橋一輝
  • Organizer: 日本天文学会 2021年 春季年会
• [Presentation] ALMA observations of Lyman alpha blobs at z=3.1 (2018)
  • Author(s): Yuichi Matsuda
  • Organizer: Tokyo Spring Cosmic Lyman-Alpha Workshop (Sakura CLAW)
  • Int'l Joint Research
• [Presentation] アルマ望遠鏡による z=3 巨大水素ガス天体のサブミリ連続波観測 (2017)
  • Author(s): 松田有一
  • Organizer: 日本天文学会
• [Presentation] The environment of submillimetre galaxies (2017)
  • Author(s): Yuichi Matsuda
  • Organizer: SMG20 - Twenty years of Submillimetre Galaxies: Star-forming galaxies at high redshifts.
  • Int'l Joint Research