Precise verification of galactic cosmic-ray propagation models by high-precision aerogel Cherenkov imaging

• Project/Area Number: 21K03584
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: Chiba University
• Principal Investigator: Tabata Makoto 千葉大学, 大学院理学研究院, 特任研究員 (10573280)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Project Status: Completed (Fiscal Year 2023)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2023: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2022: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2021: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: シリカエアロゲル / チェレンコフ輻射体 / リングイメージングチェレンコフ検出器 / 屈折率 / 透過率 / 宇宙線 / HELIX / 放射線検出器 / チェレンコフ検出器 / 宇宙線同位体比 / 宇宙線実験

Outline of Research at the Start

未解明の銀河宇宙線伝播機構の理論モデルに強い制限を与えるため、核子あたり1～10GeVの高エネルギー宇宙線の軽元素同位体存在比（特にBe-10/Be-9）のエネルギー依存性を高統計精度で精密測定する。長期気球に荷電粒子測定システムを搭載し、一次宇宙線の高統計データを収集する。宇宙線粒子の運動量と速度の測定から質量を4σ以上の分解能で決定し、同位体核種を同定する。高性能なリングイメージングチェレンコフ検出器を開発し、高エネルギー領域において粒子の速度を0.1%の精度で決定する。幅広いエネルギー領域に対応するため、屈折率が1.15および1.03のシリカエアロゲルを輻射体として開発する。

Outline of Final Research Achievements

A new silica aerogel as a radiator has been developed to upgrade a Cherenkov detector, which will be installed in a long-term balloon orbiting polar regions and identifies direct cosmic charged nuclides outside the atmosphere. Cherenkov detectors need to yield more Cherenkov light emitted from aerogels to identify cosmic-ray nuclides accurately. Light propagation in aerogels strongly depends on their physical properties, such as refractive index and optical transparency. The most transparent hydrophobic aerogel to date, with a precisely controlled refractive index of 1.03, has been successfully produced, and essential research for employing the aerogel in the detector has been completed.

Academic Significance and Societal Importance of the Research Achievements

銀河系内における宇宙線の伝播機構は未だ完全には解明されておらず複数の理論モデルが提案されているが、観測データの不足によりモデルの正当性を評価できていない。高エネルギー領域においては宇宙線粒子の軽元素同位体存在比に対して各々の理論モデルが異なる予言を与え、その精密測定は伝播機構の解明への鍵となる。本研究で新たに開発した屈折率1.03のエアロゲルを実装したチェレンコフ検出器を用いて観測を進めることにより、理論モデルに強い制限を与えることができる。また、この屈折率のエアロゲルは汎用性が高く、様々なチェレンコフ検出器への応用が期待できる。

Research Products

• [Int'l Joint Research] McGill University/Queen's University(カナダ)
• [Int'l Joint Research] University of Chicago(米国)
• [Int'l Joint Research] Queen's University/McGill University(カナダ)
• [Int'l Joint Research] University of Chicago(米国)
• [Int'l Joint Research] Queen's University/McGill University(カナダ)
• [Int'l Joint Research] University of Chicago(米国)
• [Journal Article] The High Energy Light Isotope eXperiment program of direct cosmic-ray studies (2024)
  • Author(s): Coutu S.、Allison P.S.、Baiocchi M.、Beatty J.J.、Beaufore L.、Calderon D.H.、Castano A.G.、Chen Y.、Green N.、Hanna D.、Jeon H.B.、Klein S.B.、Kunkler B.、Lang M.、Mbarek R.、McBride K.、Mognet S.I.、Musser J.、Nutter S.、O'Brien S.、Park N.、Powledge K.M.、Sakai K.、Tabata M.、et al.
  • Journal Title: Journal of Instrumentation Volume: 19 Issue: 01 Pages: C01025-C01025
  • DOI: 10.1088/1748-0221/19/01/c01025
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Electron-beam calibration of aerogel tiles for the HELIX RICH detector (2023)
  • Author(s): Allison P.、Baiocchi M.、Beatty J.J.、Beaufore L.、Calderone D.H.、Chen Y.、Coutu S.、Ellingwood E.、Green N.、Hanna D.、Jeon H.B.、Mbarek R.、McBride K.、Mognet I.、Musser J.、Nutter S.、O’Brien S.、Park N.、Rosin T.、Tabata M.、Tarle G.、Visser G.、Wakely S.P.、Yu M.
  • Journal Title: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Volume: 1055 Pages: 168549-168549
  • DOI: 10.1016/j.nima.2023.168549
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Cosmic-ray Isotope Measurements with HELIX (2023)
  • Author(s): Wakely S.、Allison P.S.、Baiocchi M.、Beatty J.J.、Beaufore L.、Calderon D.H.、Castano A.G.、Chen Y.、Coutu S.、Green N.、Hanna D.、Jeon H.、Klein S.B.、Kunkler B.、Lang M.、Mbarek R.、McBride K.、Mognet I.、Musser J.、Nutter S.、O'Brien S.、Park N.、Powledge K.M.、Sakai K.、Tabata M.、et al.
  • Journal Title: Proceedings of Science Volume: 444 Pages: 118-118
  • DOI: 10.22323/1.444.0118
  • Open Access / Int'l Joint Research
• [Journal Article] The Design and Status of the HELIX Ring Imaging Cherenkov Detector and Hodoscope Systems (2023)
  • Author(s): Jeon H.、Allison P.S.、Baiocchi M.、Beatty J.J.、Beaufore L.、Calderon D.H.、Castano A.G.、Chen Y.、Coutu S.、Green N.、Hanna D.、Klein S.B.、Kunkler B.、Lang M.、Mbarek R.、McBride K.、Mognet I.、Musser J.、Nutter S.、O'Brien S.、Park N.、Powledge K.M.、Sakai K.、Tabata M.、et al.
  • Journal Title: Proceedings of Science Volume: 444 Pages: 121-121
  • DOI: 10.22323/1.444.0121
  • Open Access / Int'l Joint Research
• [Journal Article] The HELIX Drift Chamber Tracker design and implementation (2023)
  • Author(s): McBride K.、Allison P.S.、Baiocchi M.、Beatty J.J.、Beaufore L.、Calderon D.H.、Castano A.G.、Chen Y.、Coutu S.、Green N.、Hanna D.、Jeon H.、Klein S.B.、Kunkler B.、Lang M.、Mbarek R.、Mognet I.、Musser J.、Nutter S.、O'Brien S.、Park N.、Powledge K.M.、Sakai K.、Tabata M.、et al.
  • Journal Title: Proceedings of Science Volume: 444 Pages: 123-123
  • DOI: 10.22323/1.444.0123
  • Open Access / Int'l Joint Research
• [Journal Article] High-quality aerogel Cherenkov radiators recently developed in Japan (2022)
  • Author(s): Makoto Tabata
  • Journal Title: Journal of Physics: Conference Series Volume: 2374 Issue: 1 Pages: 012114-012114
  • DOI: 10.1088/1742-6596/2374/1/012114
  • Peer Reviewed / Open Access
• [Journal Article] Calibration of Aerogel Tiles for the HELIX-RICH Detector (2021)
  • Author(s): P.Allison, J.J.Beatty, L.Beaufore, Y.Chen, S.Coutu, E.Ellingwood, M.Gebhard, N.Green, D.Hanna, B.Kunkler, I.Mognet, R.Mbarek, K.McBride, K.Michaels, D.Muller, J.Musser, S.Nutter, S.O'Brien*, N.Park, T.Rosin, E.Schreyer, G.Tarle, M.Tabata, A.Tomasch, G.Visser, S.P.Wakely, T.Werner, I.Wisher, M.Yu
  • Journal Title: Proceedings of Science Volume: 395 Pages: 090-090
  • DOI: 10.22323/1.395.0090
  • Open Access / Int'l Joint Research
• [Journal Article] Cosmic-ray isotope measurements with HELIX (2021)
  • Author(s): P.Allison, J.J.Beatty, L.Beaufore, Y.Chen, S.Coutu, M.Gebhard, N.Green, D.Hanna, H.B. Jeon, B.Kunkler, M.Lang, R.Mbarek, K.McBride, I.Mognet, D.Muller, J.Musser, S.Nutter, S.O'Brien, N.Park*, Z.Siegel, M.Tabata, G.Tarle, G.Visser, S.P.Wakely, M.Yu
  • Journal Title: Proceedings of Science Volume: 395 Pages: 091-091
  • DOI: 10.22323/1.395.0091
  • Open Access / Int'l Joint Research
• [Journal Article] High-quality aerogel Cherenkov radiators recently developed in Japan (2021)
  • Author(s): Makoto Tabata
  • Journal Title: Journal of Physics: Conference Series Volume: －
  • Peer Reviewed / Open Access
• [Presentation] High-quality aerogel Cherenkov radiators recently developed in Japan (2021)
  • Author(s): Makoto Tabata
  • Organizer: 5th International Conference on Technology and Instrumentation in Particle Physics (TIPP2021)
  • Int'l Joint Research