Study on chemical composition of high-redshift quasars

• Project/Area Number: 18K13577
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 16010:Astronomy-related
• Research Institution: The University of Tokyo
• Principal Investigator: Nishimura Yuri 東京大学, 大学院理学系研究科(理学部), 特任研究員 (90816191)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2021: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2020: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
• Keywords: 銀河進化 / 星間化学 / クェーサー / 高赤方偏移銀河 / 電波天文学 / 銀河形成 / 星間物質 / 星形成

Outline of Final Research Achievements

Molecular lines observed with radio telescopes offer us insights into physical and chemical properties of the interstellar medium of galaxies. Using Atacama Large Millimeter/submillimeter Array (ALMA), we conducted a high-sensitivity and high-resolution observation toward a gravitationally-lensed quasar, the Cloverleaf, at z=2.56 (corresponding to 2.5 billion years after Big Bang). The observation successfully revealed the distribution of key molecular species in the Cloverleaf for the first time. We found the presence of chemically-differentiated regions near the nucleus and a rotating structure with a considerably high gas fraction.

Academic Significance and Societal Importance of the Research Achievements

銀河の観測的研究では、遠くのものほど小さく暗く見えるため、遠方にある銀河はどうしても近傍にある銀河と比べて詳細を調べることがより困難になる。近年の望遠鏡の技術的な進歩、とりわけALMA望遠鏡の高感度・高空間分解能は、遠方天体での分子スペクトル線の観測可能性を大きく切り拓いた。この状況の下、銀河の分子化学組成とそれを構造や力学と対応づける研究は黎明期を迎えている。この研究では、宇宙の歴史を通じて最も著しく星形成が行われる時代の代表的な銀河について、かつてない高感度観測で分子化学組成を明らかにした。この結果は、今後より多数の銀河に研究が拡張される際のベンチマークとして役立てられる。

Research Products

• [Int'l Joint Research] Chalmers University of Technology(スウェーデン)
• [Int'l Joint Research] Chalmers University of Technology(スウェーデン)
• [Int'l Joint Research] Chalmers University of Technology(スウェーデン)
• [Int'l Joint Research] Chalmers University of Technology(スウェーデン)
• [Journal Article] Central concentration of warm and dense molecular gas in a strongly lensed submillimeter galaxy at z = 6 (2022)
  • Author(s): Tsujita Akiyoshi、Tadaki Ken-ichi、Kohno Kotaro、Hatsukade Bunyo、Egusa Fumi、Tamura Yoichi、Nishimura Yuri、Zavala Jorge、Saito Toshiki、Umehata Hideki、Lee Minju M
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 74 Issue: 6 Pages: 1429-1440
  • DOI: 10.1093/pasj/psac082
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Detection of nitrogen and oxygen in a galaxy at the end of reionization (2022)
  • Author(s): Tadaki Ken-ichi、Tsujita Akiyoshi、Tamura Yoichi、Kohno Kotaro、Hatsukade Bunyo、Iono Daisuke、Lee Minju M、Matsuda Yuichi、Michiyama Tomonari、Nagao Tohru、Nakanishi Kouichiro、Nishimura Yuri、Saito Toshiki、Umehata Hideki、Zavala Jorge
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 74 Issue: 3 Pages: L9-L16
  • DOI: 10.1093/pasj/psac018
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] AGN-driven Cold Gas Outflow of NGC 1068 Characterized by Dissociation-Sensitive Molecules (2022)
  • Author(s): Toshiki Saito, Shuro Takano, Nanase Harada, Taku Nakajima, Eva Schinnerer, Daizhong Liu, Akio Taniguchi, Takuma Izumi, Yumi Watanabe, Kazuharu Bamba, Kotaro Kohno, Yuri Nishimura, Sophia Stuber, Tomoka Tosaki
  • Journal Title: The Astrophysical Journal Volume: 935 Issue: 2 Pages: 155-155
  • DOI: 10.3847/1538-4357/ac80ff
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] APEX and NOEMA observations of H2S in nearby luminous galaxies and the ULIRG Mrk 231 (2022)
  • Author(s): Sato M. T.、Aalto S.、Kohno K.、Koenig S.、Harada N.、Viti S.、Izumi T.、Nishimura Y.、Gorski M.
  • Journal Title: Astronomy & Astrophysics Volume: 660 Pages: A82-A82
  • DOI: 10.1051/0004-6361/202141260
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The Kiloparsec-scale Neutral Atomic Carbon Outflow in the Nearby Type 2 Seyfert Galaxy NGC 1068: Evidence for Negative AGN Feedback (2022)
  • Author(s): Toshiki Saito, Shuro Takano, Nanase Harada, Taku Nakajima, Eva Schinnerer, Daizhong Liu, Akio Taniguchi, Takuma Izumi, Yumi Watanabe, Kazuharu Bamba, Eric Herbs, Kotaro Kohno, Yuri Nishimura, Sophia Stuber, Yoichi Tamura, and Tomoka Tosaki
  • Journal Title: The Astrophysical Journal Letters Volume: 927 Issue: 2 Pages: L32-L32
  • DOI: 10.3847/2041-8213/ac59ae
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] ALCHEMI, an ALMA Comprehensive High-resolution Extragalactic Molecular Inventory (2021)
  • Author(s): Martin S.、Mangum J. G.、Harada N.、Costagliola F.、Sakamoto K.、Muller S.、Aladro R.、Tanaka K.、Yoshimura Y.、Nakanishi K.、Herrero-Illana R.、Muehle S.、Aalto S.、Behrens E.、Colzi L.、Emig K. L.、Fuller G. A.、Garcia-Burillo S.、Greve T. R.、Henkel C.、Holdship J.、Humire P.、Hunt L.、Izumi T.、Kohno K.他
  • Journal Title: Astronomy and Astrophysics Volume: 656 Pages: A46-A46
  • DOI: 10.1051/0004-6361/202141567
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Starburst Energy Feedback Seen through HCO+/HOC+ Emission in NGC 253 from ALCHEMI (2021)
  • Author(s): Harada Nanase、Martin Sergio、Mangum Jeffrey G.、Sakamoto Kazushi、Muller Sebastien、Tanaka Kunihiko、Nakanishi Kouichiro、Herrero-Illana Rubin、Yoshimura Yuki、Muehle Stefanie、Aladro Rebeca、Colzi Laura、Rivilla Victor M.、Aalto Susanne、Behrens Erica、Henkel Christian、Holdship Jonathan、Humire P. K.他
  • Journal Title: The Astrophysical Journal Volume: 923 Issue: 1 Pages: 24-24
  • DOI: 10.3847/1538-4357/ac26b8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] CON-quest: Searching for the most obscured galaxy nuclei (2021)
  • Author(s): Falstad, Aalto, Koenig, Onishi, Muller, Gorski, Sato, Stanley, Combes, Gonzalez-Alfonso, Mangum, Evans, Barcos-Munoz, Privon, Linden, Diaz-Santos, Martin, Sakamoto, Harada, Fuller, Gallagher, van der Werf, Viti, Greve, Garcia-Burillo, Henkel, Imanishi, Izumi, Nishimura, Ricci, Muehle
  • Journal Title: Astronomy and Astrophysics Volume: －
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] LEGO ? II. A 3?mm molecular line study covering 100?pc of one of the most actively star-forming portions within the Milky Way disc (2020)
  • Author(s): Barnes A T, Kauffmann J, Bigiel F, Brinkmann N, Colombo D, Guzman A E, Kim W J, Szucs L, Wakelam V, Aalto S, Albertsson T, Evans N J, Glover S C O, Goldsmith P F, Kramer C, Menten K, Nishimura Y, Viti S, Watanabe Y, Weiss A, Wienen M, Wiesemeyer H, Wyrowski F
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 497 Issue: 2 Pages: 1972-2001
  • DOI: 10.1093/mnras/staa1814
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Chemistry and physics of a low-metallicity hot core in the Large Magellanic Cloud (2020)
  • Author(s): Shimonishi, T., Das, A., Sakai, N., Tanaka, K. E. I., Aikawa, Y., Onaka, T., Watanabe, Y., and Nishimura, Y.
  • Journal Title: The Astrophysical Journal Volume: 891 Issue: 2 Pages: 164-164
  • DOI: 10.3847/1538-4357/ab6e6b
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Molecular Gas Density Measured with H2CO and CS toward a Spiral Arm of M51 (2019)
  • Author(s): Nishimura Yuri、Watanabe Yoshimasa、Harada Nanase、Kohno Kotaro、Yamamoto Satoshi
  • Journal Title: The Astrophysical Journal Volume: 879 Issue: 2 Pages: 65-65
  • DOI: 10.3847/1538-4357/ab24d3
  • Peer Reviewed
• [Journal Article] A 3 mm Spectral Line Survey toward the Barred Spiral Galaxy NGC 3627 (2019)
  • Author(s): Watanabe Yoshimasa、Nishimura Yuri、Sorai Kazuo、Sakai Nami、Kuno Nario、Yamamoto Satoshi
  • Journal Title: The Astrophysical Journal Supplement Series Volume: 242 Issue: 2 Pages: 26-26
  • DOI: 10.3847/1538-4365/ab1d63
  • Peer Reviewed
• [Journal Article] Molecular-cloud-scale Chemical Composition. III. Constraints of Average Physical Properties through Chemical Models (2019)
  • Author(s): Harada Nanase、Nishimura Yuri、Watanabe Yoshimasa、Yamamoto Satoshi、Aikawa Yuri、Sakai Nami、Shimonishi Takashi
  • Journal Title: The Astrophysical Journal Volume: 871 Issue: 2 Pages: 238-238
  • DOI: 10.3847/1538-4357/aaf72a
  • Peer Reviewed / Int'l Joint Research
• [Presentation] CONquest + CONtrail: chemical characterization of CONs and outflows (2023)
  • Author(s): Yuri Nishimura
  • Organizer: CONquest workshop 2023
  • Int'l Joint Research / Invited
• [Presentation] ALMA Band 3 line survey toward the Cloverleaf quasar at z~2.56 (2023)
  • Author(s): Yuri Nishimura
  • Organizer: 2023 Kavli-IAU Astrochemistry Symposium: Astrochemistry VIII - From the First Galaxies to the Formation of Habitable Worlds
  • Int'l Joint Research
• [Presentation] ALMA Band 3 line survey oward the Cloverleaf quasar at z~2.56 (2022)
  • Author(s): Yuri Nishimura
  • Organizer: Molecules in extreme environments: Near and Far
  • Int'l Joint Research
• [Presentation] ALMA Band 3 line survey toward the Cloverleaf quasar at z~2.56 (2022)
  • Author(s): Yuri Nishimura
  • Organizer: A half century of millimeter and submillimeter astronomy: Impact on astronomy/astrophysics and the future
  • Int'l Joint Research
• [Presentation] Spatially and Spectrally resolved HCN/HCO+ ratio in the CON-quest galaxies (2022)
  • Author(s): Yuri Nishimura
  • Organizer: CON-quest workshop 2022
  • Int'l Joint Research / Invited
• [Presentation] Spatially and Spectrally resolved HCN/HCO+ ratio in U/LIRGs from the CONquest sample (2021)
  • Author(s): Yuri Nishimura
  • Organizer: Astrochemical Frontiers 2021
  • Int'l Joint Research / Invited
• [Presentation] Spatially and Spectrally resolved HCN/HCO+ ratio in U/LIRGs from the CONquest sample (2021)
  • Author(s): 西村優里
  • Organizer: 第5回 FORCE研究会「埋もれたAGNの宇宙論的進化」
• [Presentation] Spatially and Spectrally resolved HCN/HCO+ ratio in U/LIRGs: Mechanisms to elevate the line ratio (2021)
  • Author(s): 西村優里
  • Organizer: ALMA Grant Fellow Symposium 2021
• [Presentation] Spatially and spectrally resolved HCN/HCO+ ratios in ultraluminous and lumi- nous infrared galaxies from the CON-quest sample (2021)
  • Author(s): Yuri Nishimura
  • Organizer: 日本天文学会 2021年春季年会
• [Presentation] 重力レンズクェーサーCloverleafにおける350 GHz帯分子輝線サーベイ (2021)
  • Author(s): Yuri Nishimura
  • Organizer: 日本天文学会 2021年春季年会
• [Presentation] Spatially and spectrally resolved HCN/HCO+ ratios in the CONquest galaxies (2021)
  • Author(s): Yuri Nishimura
  • Organizer: CON-quest workshop 2021
  • Int'l Joint Research
• [Presentation] Spatially and spectrally resolved HCN/HCO+ ratio in luminous infrared galaxies 
from the CON-quest sample (2020)
  • Author(s): Yuri Nishimura
  • Organizer: ALMA Grant Fellow Symposium 2020
• [Presentation] Multi-line spectroscopy to assess molecular cloud properties (2020)
  • Author(s): Yuri Nishimura
  • Organizer: East-Asian ALMA science workshop
  • Int'l Joint Research / Invited
• [Presentation] ALMA rest-frame 0.8 mm-band line survey in the Cloverleaf (2020)
  • Author(s): Yuri Nishimura
  • Organizer: ALMA workshop “The blind search for hidden galaxies in an abundant line of sight”
  • Int'l Joint Research / Invited
• [Presentation] Molecular-cloud-scale multi-line mapping toward the Galactic molecular cloud W3(OH) in the 3 mm and 0.8 mm band (2019)
  • Author(s): Yuri Nishimura
  • Organizer: Linking the Milky Way and Nearby Galaxies
  • Int'l Joint Research
• [Presentation] Molecular-Cloud-Scale Multi-Line Imaging Toward W3(OH) in the 3 mm and 0.8 mm Bands (2019)
  • Author(s): Yuri Nishimura
  • Organizer: Behind the Curtain of Dust III
  • Int'l Joint Research / Invited
• [Presentation] 分子輝線から銀河を理解するための”分子雲”の星間化学 (2019)
  • Author(s): ⻄村優里
  • Organizer: 第49回 天文・天体物理若手 夏の学校
  • Invited
• [Presentation] Molecular-Cloud-Scale Chemical Composition: Observations of Nearby Galaxies and Galactic Clouds (2019)
  • Author(s): Yuri Nishimura
  • Organizer: ALMA Grant Fellow Symposium 2019
• [Presentation] Molecular-cloud-scale multi-line imaging toward W3(OH) in the 0.8 mm band (2019)
  • Author(s): 西村優里、渡邉祥正、原田ななせ、吉村勇紀、河野孝太郎、山本智
  • Organizer: 日本天文学会2019年春季年会
• [Presentation] Molecular composition of local dwarf galaxies: Astrochemistry in low-metallicity environments (2018)
  • Author(s): Yuri Nishimura
  • Organizer: IAU Symposium 344 - Dwarf Galaxies: From the Deep Universe to the Present
  • Int'l Joint Research
• [Presentation] Molecular ISM of galaxies from local dwarfs to high-redshifts (2018)
  • Author(s): Yuri Nishimura
  • Organizer: Hendrik van de Hulst Centennial Symposium - The Interstellar Medium of Galaxies: Status and Future Perspectives
  • Int'l Joint Research
• [Presentation] Galactic diffuse molecular gas detected in absorption toward ALMA calibrator sources (2018)
  • Author(s): Yuri Nishimura
  • Organizer: Cosmic Shadow 2018 ~クェーサー吸収線系でみる宇宙~