Improving the sensitivity of the next-generation gamma-ray observatory CTA with higher collection efficiency of atmospheric Cherenkov photons

• Project/Area Number: 25707017
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University
• Principal Investigator: Okumura Akira 名古屋大学, 宇宙地球環境研究所, 講師 (90645011)
• Project Period (FY): 2013-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥22,490,000 (Direct Cost: ¥17,300,000、Indirect Cost: ¥5,190,000); Fiscal Year 2016: ¥7,150,000 (Direct Cost: ¥5,500,000、Indirect Cost: ¥1,650,000); Fiscal Year 2015: ¥6,630,000 (Direct Cost: ¥5,100,000、Indirect Cost: ¥1,530,000); Fiscal Year 2014: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2013: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
• Keywords: ガンマ線 / 宇宙線 / チェレンコフ望遠鏡アレイ / CTA / Cherenkov Telescope Aray / ウィンストンコーン / ガンマ線天文学 / 光検出器 / 光学 / 光線追跡 / 宇宙線物理学

Outline of Final Research Achievements

We have developed a prototype hexagonal light concentrator for the Large-Sized Telescopes of the Cherenkov Telescope Array. To maximize the photodetection efficiency of the focal-plane camera pixels for atmospheric Cherenkov photons and to lower the energy threshold, a specular film with a very high reflectance of 92-99% has been developed to cover the inner surfaces of the light concentrators. The prototype has a relative anode sensitivity (which can be roughly regarded as collection efficiency) of about 95 to 105% at the most important angles of incidence.

Research Products

• [Int'l Joint Research] マックスブランク核物理学研究所/マックスプランク物理学研究所(ドイツ)
• [Int'l Joint Research] マックスプランク核物理学研究所/マックスプランク物理学研究所(ドイツ)
• [Int'l Joint Research] レスター大学(英国)
• [Int'l Joint Research] パリ天文台(フランス)
• [Journal Article] Prototyping hexagonal light concentrators using high-reflectance specular films for the large-sized telescopes of the Cherenkov Telescope Array (2017)
  • Author(s): Okumura A.、Dang T.V.、Ono S.、Tanaka S.、Hayashida M.、Hinton J.、Katagiri H.、Noda K.、Teshima M.、Yamamoto T.、Yoshida T.
  • Journal Title: Journal of Instrumentation Volume: 12 Issue: 12 Pages: P12008-P12008
  • DOI: 10.1088/1748-0221/12/12/p12008
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Science with the Cherenkov Telescope Array (2017)
  • Author(s): The Cherenkov Telescope Array Consortium
  • Journal Title: arXiv:1709.07997 Volume: N/A
  • Open Access
• [Journal Article] ROBAST: Development of a ROOT-based ray-tracing library for cosmic-ray telescopes and its applications in the Cherenkov Telescope Array (2016)
  • Author(s): Akira Okumura, Koji Noda, and Cameron Rulten
  • Journal Title: Astroparticle Physics Volume: 76
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Prototyping of Hexagonal Light Concentrators for the Large-Sized Telescopes of the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura, Sakiya Ono, Syunya Tanaka, Masaaki Hayashida, Hideaki Katagiri, and Tatsuo Yoshida
  • Journal Title: Proceedings of the 34th International Cosmic Ray Conference Volume: N/A
  • Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] ROBAST: Development of a Non-Sequential Ray-Tracing Simulation Library and its Applications in the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura, Koji Noda, and Cameron Rulten
  • Journal Title: Proceedings of the 34th International Cosmic Ray Conference Volume: N/A
  • Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Introducing the CTA concept (2013)
  • Author(s): Acharya, et al.
  • Journal Title: Astroparticle Physics Volume: 43 Pages: 3-18
  • DOI: 10.1016/j.astropartphys.2013.01.007
  • Peer Reviewed
• [Presentation] 地上ガンマ線望遠鏡 CTA のための高効率な集光装置の試作 (2018)
  • Author(s): 奥村曉
  • Organizer: 日本物理学会 第73回年次大会
• [Presentation] CTA報告130：全体報告 (2018)
  • Author(s): 手嶋政廣
  • Organizer: 日本物理学会 第73回年次大会
• [Presentation] CTA大口径望遠鏡初号機の焦点面カメラ統合試験 (2018)
  • Author(s): 平子丈
  • Organizer: 日本天文学会 2018年春季年会
• [Presentation] Cherenkov Telescope Array (CTA) 計画：全体報告(14) (2018)
  • Author(s): 窪秀利
  • Organizer: 日本天文学会 2018年春季年会
• [Presentation] CTA報告110：焦点面光検出器の光検出効率改善に向けた集光装置の開発 (2016)
  • Author(s): 奥村曉
  • Organizer: 日本物理学会 2016 年秋季大会
  • Place of Presentation: 宮崎大学
  • Year and Date: 2016-09-21
• [Presentation] Prototyping of Hexagonal Light Concentrators for the Large-Sized Telescopes of the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura
  • Organizer: The 34th International Cosmic Ray Conference
  • Place of Presentation: オランダ ハーグ
  • Year and Date: 2015-07-30 – 2015-08-06
• [Presentation] ROBAST: Development of a Non-sequential Ray-tracing Simulation Library and its Applications in the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura
  • Organizer: The 34th International Cosmic Ray Conference
  • Place of Presentation: オランダ ハーグ
  • Year and Date: 2015-07-30 – 2015-08-06
• [Presentation] ROBAST: Development of a Non-Sequential Ray-Tracing Simulation Library and its Applications in the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura, Koji Noda, and Cameron Rulten
  • Organizer: The 34th International Cosmic Ray Conference
  • Place of Presentation: The Hague, The Netherlands
  • Year and Date: 2015-07-30
  • Int'l Joint Research
• [Presentation] Prototyping of Hexagonal Light Concentrators for the Large-Sized Telescopes of the Cherenkov Telescope Array (2015)
  • Author(s): Akira Okumura, Sakiya Ono, Syunya Tanaka, Masaaki Hayashida, Hideaki Katagiri, and Tatsuo Yoshida
  • Organizer: The 34th International Cosmic Ray Conference
  • Place of Presentation: The Hague, The Netherlands
  • Year and Date: 2015-07-30
  • Int'l Joint Research
• [Presentation] CTA報告92: CTA 大口径望遠鏡初号機用ライトガイドの開発 (2015)
  • Author(s): 小野祥弥
  • Organizer: 日本物理学会 第70回年次大会
  • Place of Presentation: 早稲田大学
  • Year and Date: 2015-03-21
• [Presentation] CTA報告71：CTA大口径望遠鏡用ライトガイドの試作機性能評価及び形状最適化に向けた研究 (2014)
  • Author(s): 田中駿也 他
  • Organizer: 日本物理学会 第69回年次大会
  • Place of Presentation: 東海大学
• [Presentation] Cherenkov Telescope Array Large Size Telescope Optics (2013)
  • Author(s): M. Teshima et al.
  • Organizer: The 33rd International Cosmic Ray Conference
  • Place of Presentation: ブラジル、リオデジャネイロ
• [Presentation] The Cherenkov Telescope Array Large Size Telescope (2013)
  • Author(s): G. Ambrosi et al.
  • Organizer: The 33rd International Cosmic Ray Conference
  • Place of Presentation: ブラジル、リオデジャネイロ
• [Presentation] CTA報告62：CTA 大口径望遠鏡用ライトガイドの試作機性能評価及び大量生産に向けた開発 (2013)
  • Author(s): 田中駿也 他
  • Organizer: 日本物理学会 2013年秋季大会
  • Place of Presentation: 高知大学
• [Remarks]
  • URL: http://www.cta-observatory.jp/
• [Remarks]
  • URL: https://www.cta-observatory.org
• [Remarks] ROBAST
  • URL: https://robast.github.io/
• [Remarks] Cherenkov Telescope Array Japan
  • URL: http://www.cta-observatory.jp/index.html