Probing small scale cosmology with high-resolution radio observation

• Project/Area Number: 17H02868
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Astronomy
• Research Institution: Kindai University
• Principal Investigator: Inoue Kaiki 近畿大学, 理工学部, 教授 (70388495)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000); Fiscal Year 2020: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2019: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2018: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2017: ¥6,370,000 (Direct Cost: ¥4,900,000、Indirect Cost: ¥1,470,000)
• Keywords: 重力レンズ / ダークマター / クエーサー / 銀河 / 宇宙論 / 銀河群 / 矮小銀河 / 構造形成 / ボイド / 大規模構造 / 4重像重力レンズ / 長寿命荷電大質量粒子 / フラックス比異常 / 小スケール問題 / サブハロー / ALMA / 暗黒矮小銀河 / 電波観測

Outline of Final Research Achievements

We developed a new algorithm for constructing a gravitational lens model from an image of a lensed quasar. Compared to the previous algorithms, our algorithm is much suitable for reconstructing a complex gravitational potential and a source with a complex surface brightness distribution. We applied our new algorithm to the image of a lensed quasar that we observed with the ALMA telescope. Then we found that the measured amplitude of fluctuations of matter density is too large if only subhaloes in the lensing galaxy are taken into account. We also developed a new tool for detecting gravitational lenses. We discovered many candidates of gravitational lenses in the HSC galaxy catalogue.

Academic Significance and Societal Importance of the Research Achievements

宇宙に存在するダークマター(光でみえない質量)の有力な候補がCDM(冷たいダークマター)である。ダークマターが全てCDMであれば、天の川銀河のような大質量の銀河の中に、多くの矮小銀河が含まれていることが分かっている。しかし、今までの観測からは少数の矮小銀河しかみつかっていない。また、銀河間空間にも多くの矮小銀河があることが理論的に分かっているが、未だ観測されていない。我々の重力レンズ天体の観測結果は、従来の観測方法では検出できないほど暗い矮小銀河が銀河間空間にも数多くあることを示唆している。ダークマターモデルの宇宙論的な制限として新しい結果であり、意義深いものと考えられる。

Research Products

• [Journal Article] Survey of Gravitationally Lensed Objects in HSC Imaging (SuGOHI) VII. Discovery and confirmation of three strongly lensed quasars (2021)
  • Author(s): Jaelani Anton T、Rusu Cristian E、Kayo Issha、More Anupreeta、Sonnenfeld Alessandro、Silverman John D、Schramm Malte、Anguita Timo、Inada Naohisa、Kondo Daichi、Schechter Paul L、Lee Khee-Gan、Oguri Masamune、Chan James H H、Wong Kenneth C、Inoue Kaiki T
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 502 Issue: 1 Pages: 1487-1493
  • DOI: 10.1093/mnras/stab145
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Survey of Gravitationally lensed Objects in HSC Imaging (SuGOHI) ? V. Group-to-cluster scale lens search from the HSC?SSP Survey (2020)
  • Author(s): Jaelani Anton T、More Anupreeta、Oguri Masamune、Sonnenfeld Alessandro、Suyu Sherry H、Rusu Cristian E、Wong Kenneth C、Chan James H H、Kayo Issha、Lee Chien-Hsiu、Chao Dani C-Y、Coupon Jean、Inoue Kaiki T、Futamase Toshifumi
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 495 Issue: 1 Pages: 1291-1310
  • DOI: 10.1093/mnras/staa1062
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] ALMA 50-parsec-resolution Imaging of Jet-ISM Interaction in the Lensed Quasar MG J0414+0534 (2020)
  • Author(s): Inoue Kaiki Taro、Matsushita Satoki、Nakanishi Kouichiro、Minezaki Takeo
  • Journal Title: The Astrophysical Journal Volume: 892 Issue: 2 Pages: L18-L18
  • DOI: 10.3847/2041-8213/ab7b7e
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Discovery of an unusually compact lensed Lyman-break galaxy from the Hyper Suprime-Cam Survey (2020)
  • Author(s): Jaelani Anton T、More Anupreeta、Sonnenfeld Alessandro、Oguri Masamune、Rusu Cristian E、Wong Kenneth C、Chan James H H、Suyu Sherry H、Kayo Issha、Lee Chien-Hsiu、Inoue Kaiki T
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 494 Issue: 3 Pages: 3156-3165
  • DOI: 10.1093/mnras/staa583
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Detecting sub-lunar mass compact objects toward the Local Group galaxies (2018)
  • Author(s): Kaiki Taro Inoue
  • Journal Title: New Astronomy Volume: 58
  • Peer Reviewed
• [Journal Article] Constraints on long-lived electrically charged massive particles from anomalous strong lens systems (2017)
  • Author(s): Kamada Ayuki、Inoue Kaiki Taro、Kohri Kazunori、Takahashi Tomo
  • Journal Title: Journal of Cosmology and Astroparticle Physics Volume: 2017 Issue: 11 Pages: 008-008
  • DOI: 10.1088/1475-7516/2017/11/008
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Line-of-Sight Lensing - a New Window to Dark Matter and Distant Dark Dwarf Galaxies (2021)
  • Author(s): Kaiki Taro Inoue
  • Organizer: Time-Domain Cosmology with Strong Gravitational Lensing
  • Int'l Joint Research
• [Presentation] Mining Strong Lensing Survey (2021)
  • Author(s): Anton Timur Jaelani
  • Organizer: 2021年春季日本天文学会
• [Presentation] 重力レンズクエーサーで切り拓く小スケール宇宙論-レンジングパワースペクトルの測定 (2021)
  • Author(s): Kaiki Taro Inoue, Takeo Minezaki, Satoshi Matsushita, Koichiro Nakanishi
  • Organizer: 2021年春季日本天文学会
• [Presentation] 重力レンズクエーサーによる小密度ゆらぎの測定 (2020)
  • Author(s): Kaiki Taro Inoue, Takeo Minezaki, Satoshi Matsushita, Koichiro Nakanishi
  • Organizer: 2020年秋季日本天文学会
• [Presentation] Introduction to (Strong) Gravitational Lensing (2020)
  • Author(s): Anton Timur Jaelani
  • Organizer: SSGC 2020
• [Presentation] \ALMA Resolves Jet-driven Molecular Out ows in the Lensed QSO MGJ 0414+0534 (2019)
  • Author(s): Kaiki Taro Inoue, Satoki Matsushita, Kohichiro Nakanishi and Takeo Minezaki
  • Organizer: 日本天文学会秋季年会
• [Presentation] Finding New Strong Gravitational Lens Systems from HSC Survey (2019)
  • Author(s): Anton T. Jaelani, Anupreeta More, Alessandro Sonnenfeld, Masamune Oguri, Kenneth C.Wong, James H.H. Chan, Cristian E. Rusu, Sherry H. Suyu, Issha Kayo
  • Organizer: 日本天文学会秋季年会
• [Presentation] Detecting Sub-lunar Mass Compact Objects toward the Local Group Galaxies (2018)
  • Author(s): Kaiki Taro Inoue
  • Organizer: 理論研究部理論コロキウム
  • Invited
• [Presentation] クェーサーMG0751+2716 の重力レンズモデル (2018)
  • Author(s): Yasuo, Horiguchi, Kaiki Taro Inoue
  • Organizer: 日本天文学会
• [Presentation] トラフレンズによる10kpc 以下の密度ゆらぎの制限 (2018)
  • Author(s): Kaiki Taro Inoue, Tomoaki Ishiyama, Takashi Hamana
  • Organizer: 日本天文学会
• [Presentation] 拡がった光源に対する重力レンズ効果のモデリング (2017)
  • Author(s): Tomoyuki Shigeno, Kaiki Taro Inoue
  • Organizer: 日本天文学会
• [Presentation] 重力レンズで探る暗黒矮小銀河とダークマター (2017)
  • Author(s): Kaiki Taro Inoue
  • Organizer: ダークマター研究会
  • Invited
• [Presentation] Probing Dark Dwarf Galaxies with Gravitational Lensing (2017)
  • Author(s): Kaiki Taro Inoue
  • Organizer: ALMA long Baseline Workshop
  • Int'l Joint Research
• [Remarks] ALMA Resolves Gas Impacted by Young Jets
  • URL: https://www.cosmology.jp/english/research_highlight/475
• [Remarks] アルマ望遠鏡でブラックホールジェットと星間ガスの衝突を観測
  • URL: https://www.kindai.ac.jp/news-pr/news-release/2020/03/019700.html