Development of large-aperture emulsion gamma-ray telescopes for high-angular resolution observation of the galactic center

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H01915
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: Nagoya University
• Principal Investigator: Rokujo Hiroki 名古屋大学, 未来材料・システム研究所, 特任助教 (00725814)
• Co-Investigator(Kenkyū-buntansha): 伊代野 淳 岡山理科大学, 理学部, 教授 (10211757)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ガンマ線天文学 / 宇宙線 / 暗黒物質 / 高エネルギー天文学 / イメージング / 気球実験 / 原子核乾板 / 飛跡検出器

Outline of Final Research Achievements

For the next balloon experiment (postponed two years due to COVID-19, to be conducted in spring 2023), the following R&Ds were conducted to realize the aperture area expansion of the world's highest angular-resolution gamma-ray telescope consisting of nuclear emulsion. 1) Construction and installation of a new large-scale nuclear emulsion gel production system at Nagoya University. 2) New construction and installation of roll-to-roll nuclear emulsion film coating system at Nagoya University. 3) Demonstration of the performance of the new nuclear emulsion through rehearsal of atmospheric gamma-ray observation at Mt. Norikura. 4) Mass production of nuclear emulsion and assembling large-aperture converters through continuous and stable operation of the new facilities. 5) Development of 5-m-long balloon-style pressure vessel gondolas. 6) Development and introduction of solution physical development method. 7) Completion of final preparations for Australian balloon experiment (GRAINE 2023).

Free Research Field

宇宙線物理学

Academic Significance and Societal Importance of the Research Achievements

2008年より観測を続けるフェルミγ線宇宙望遠鏡が提供する高統計観測データはγ線天文学を大きく前進させた。一方で銀河中心で特異な超過が報告されるなど未解決課題も浮かび上がっている。今後は観測データの質的改善が求められる。本研究開発により実現する原子核乾板を用いたγ線望遠鏡によってフェルミ望遠鏡の角度分解能を約1桁更新するγ線天体精密観測を可能にする。2023年に実施する気球実験により銀河中心領域1GeV帯域の世界最高解像度でのイメージングデータ提示が期待される。