Precise measurement of high-energy cosmic-ray isotopes by silica aerogel: Elucidating cosmic-ray propagation mechanism

• Project/Area Number: 18K03666
• 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): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2020: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2018: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• 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 / HELIX実験 / 宇宙線同位体比 / 宇宙線実験

Outline of Final Research Achievements

We have developed a Cherenkov detector for observing primary cosmic-ray particles outside the atmosphere by mounting it on a long-term orbiting balloon in the Earth's polar region. Cherenkov detectors detect the Cherenkov light generated when a charged particle with a relativistic velocity passes through a radiator by a photosensor. The velocity of the particle can be determined by analyzing the output signal. The performance of the Cherenkov detectors strongly depends on the optical properties, such as the refractive index and transparency of the radiator. We have succeeded in developing and mass-producing a highly transparent hydrophobic silica aerogel with a controlled refractive index. The aerogel enables the measurement of the light isotope ratio of high-energy cosmic rays, which has been difficult so far.

Academic Significance and Societal Importance of the Research Achievements

宇宙線の発見から100年以上が経つが、その銀河空間における伝播機構は未だ完全には解明されていない。様々な伝播機構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。各々の理論モデルが異なる予言を与えている、高エネルギー領域の宇宙線粒子の軽元素同位体存在比の精密測定が宇宙線伝播機構の解明の鍵となる。本研究で開発したエアロゲルによるチェレンコフ検出器を用いれば理論モデルに強い制限を与えることができる。

Research Products

• [Int'l Joint Research] McGill University/Queen's University(カナダ)
• [Int'l Joint Research] University of Chicago/University of Wisconsin-Madison/Pennsylvania State University(米国)
• [Int'l Joint Research] McGill University(カナダ)
• [Int'l Joint Research] University of Chicago/University of Wisconsin-Madison/Pennsylvania State University(米国)
• [Int'l Joint Research] University of Chicago(米国)
• [Int'l Joint Research] McGill University(カナダ)
• [Journal Article] エアロゲルの開発と応用 (2020)
  • Author(s): 田端 誠
  • Journal Title: 高エネルギーニュース Volume: 38 Pages: 124-134
  • Peer Reviewed / Open Access
• [Journal Article] Production of Silica Aerogel Radiator Tiles for the HELIX RICH Detector (2019)
  • Author(s): P.Allison, J.Beatty, L.Beaufore, Y.Chen, S.Coutu, E.Ellingwood, M.Gebhard, N.Green, D.Hanna, B.Kunkler, S.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.Wakely, T.Werner, I.Wisher, M.Yu
  • Journal Title: Proceedings of Science Volume: 358 Pages: 139-139
  • Open Access / Int'l Joint Research
• [Journal Article] Cosmic-ray Isotope Measurements with HELIX (2019)
  • Author(s): P.Allison, 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.Wakely, T.Werner, I.Wisher, M.Yu
  • Journal Title: Proceedings of Science Volume: 358 Pages: 121-121
  • Open Access / Int'l Joint Research
• [Journal Article] The Design and Construction of the HELIX RICH Detector (2019)
  • Author(s): P.Allison, 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.Wakely, T.Werner, I.Wisher*, M.Yu
  • Journal Title: Proceedings of Science Volume: 358 Pages: 152-152
  • Open Access / Int'l Joint Research
• [Journal Article] Calibration of the Aerogel Tiles for the HELIX RICH (2019)
  • Author(s): P.Allison, 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.Wakely, T.Werner, I.Wisher, M.Yu
  • Journal Title: Proceedings of Science Volume: 358 Pages: 133-133
  • Open Access / Int'l Joint Research
• [Journal Article] Developing a silica aerogel radiator for the HELIX ring-imaging Cherenkov system (2019)
  • Author(s): M. Tabata, P. Allison, J.J. Beatty, S. Coutu, M. Gebhard, N. Green, D. Hanna, B. Kunkler, M. Lang, K. McBride, S.I. Mognet, D. Muller, J. Musser, S. Nutter, N. Park, M. Schubnell, G. Tarle, A. Tomasch, G. Visser, S.P. Wakely, I. Wisher
  • Journal Title: Nuclear Instruments and Methods in Physics Research A Volume: 印刷中 Pages: 161879-161879
  • DOI: 10.1016/j.nima.2019.02.006
  • Peer Reviewed / Int'l Joint Research
• [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
• [Presentation] 南極気球による宇宙線軽元素同位体比精密測定実験HELIXに向けたリングイメージングチェレンコフ検出器のための超高屈折率シリカエアロゲル (2019)
  • Author(s): 田端 誠
  • Organizer: 日本物理学会2019年秋季大会
• [Presentation] Production of silica aerogel radiator tiles for the HELIX RICH (2019)
  • Author(s): M. Tabata, P. Allison, J.J. Beatty, L. Beaufore, Y. Chen, S. Coutu, E. Ellingwood, N. Green, D. Hanna, B. Kunkler, R. Mbarek, K. McBride, S.I. Mognet, D. Muller, J. Musser, S. Nutter, S. O'Brien, N. Park, T. Rosin, G. Tarle, A. Tomasch, G. Visser, S.P. Wakely, I. Wisher, M. Yu
  • Organizer: 36th International Cosmic Ray Conference (ICRC 2019)
  • Int'l Joint Research
• [Presentation] Silica aerogel radiator for the HELIX RICH system (2018)
  • Author(s): M. Tabata, P. Allison, J.J. Beatty, S. Coutu, M. Gebhard, N. Green, D. Hanna, B. Kunkler, M. Lang, S.I. Mognet, D. Muller, J. Musser, S. Nutter, N. Park, M. Schubnell, G. Tarle, A. Tomasch, G. Visser, S.P. Wakely, I. Wisher
  • Organizer: 10th International Workshop on Ring Imaging Cherenkov Detectors (RICH 2018)
  • Int'l Joint Research
• [Remarks] Blue dot
  • URL: http://www.ppl.phys.chiba-u.jp/~makoto/index.html