Development of extremely low-material particle tracker enabled by a conductive polymer straw

2019 Fiscal Year Final Research Report

• Project/Area Number: 16H02192
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Nishiguchi Hajime 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 准教授 (10534810)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: ミューオン / 素粒子実験 / 放射線検出器 / ガス増幅型検出器

Outline of Final Research Achievements

In this research program, we aimed to develop the detector which can explore the phenomenon in the new elementary particle standard model caused by higher energy than tera-electron-volt. This can be realized investigating the known particle's phenomenon precisely. However, known phenomenon at mega-electron-volt must be investigated carefully with a low material detector because the particle trajectory can be disrupted easily due to the multiple coulomb scattering. In this research program, extremely thin-wall straw, which is operational in vacuum, was enabled by ultra-sonic welding technique. This thin-wall straw was equipped as a tracking detector, and the detection performances were confirmed with 105 MeV electron beam in the vacuum environment. By this result, the detector R&D for COMET Phase-I was completed. And a new straw, 12 micron-thick and 5mm rad., was also enabled by new technique. Four more straw stations would be constructed to perform the COMET Phase-II experiment.

Free Research Field

素粒子物理学実験

Academic Significance and Societal Importance of the Research Achievements

本研究で開発した素粒子飛跡検出器は、真空中で動作可能な導電性薄膜比例計数管で、現在世界で最も軽い飛跡検出器である。低いエネルギーでの素粒子反応を精密に検知するには、粒子の飛跡が検出器の構成物質で散乱してしまう影響を抑制することが肝要であり、本研究の成果はその低物質量化の世界記録を達成したことに相当する。この飛跡検出器は、今後ミュー粒子崩壊の精密測定実験で用い、素粒子物理の新展開を目指す計画である。