Polarization Measurement aboard the Satellite and Solution of the Emission Mechanism of the Gamma-Ray Bursts

2012 Fiscal Year Final Research Report

• Project/Area Number: 20674002
• Research Category: Grant-in-Aid for Young Scientists (S)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Kanazawa University
• Principal Investigator: YONETOKU Daisuke 金沢大学, 数物科学系, 准教授 (40345608)
• Project Period (FY): 2008 – 2012
• Keywords: ガンマ線バースト / 偏光 / 宇宙物理 / 人工衛星 / 検出器開発 / 相対論的ジェット / 量子重力 / CPT対称性

Research Abstract

The Gamma-Ray Burst Polarimeter (GAP) was installed aboard the IKAROS solar-sail spacecraft which was launched on May 21st 2010. We realized the first gamma-ray polarimetry in the world. We detected the strong polarization in the prompt emissions of three gamma-ray bursts, and we consider that the emission mechanism is probably synchrotron radiation. Moreover, we detected possible evidence of the existence of inner structures in the relativistic jets. We could contribute to reveal the emission mechanism of gamma-ray bursts.

Research Products

• [Journal Article] Strict Limit on CPT Violation from Polarization of Gamma-Ray Burst (2012)
  • Author(s): Kenji Toma, Shinji Mukohyama, Daisuke Yonetoku, Toshio Murakami, Shuichi Gunji, Tatehiro Mihara, Yoshiyuki Morihara, Tomonori Sakashita, Takuya Takahashi, Yudai Wakashima, Hajime Yonemochi, Noriyuki Toukairin
  • Journal Title: Physical Review Letters Volume: 109 Pages: 241104
  • Peer Reviewed
• [Journal Article] Magnetic Structures in Gamma-Ray Burst Jets Probed by Gamma-Ray Polarization (2012)
  • Author(s): Daisuke Yonetoku, Toshio Murakami, Shuichi Gunji, Tatehiro Mihara, Kenji Toma, Yoshiyuki Morihara, Takuya Takahashi, Yudai Wakashima, Hajime Yonemochi, Tomonori Sakashita, Noriyuki Toukairin, Hirofumi Fujimoto, Yoshiki Kodama
  • Journal Title: The Astrophysical Journal Volume: 758 Pages: L1
  • Peer Reviewed
• [Journal Article] Detection of Gamma-Ray Polarization in Prompt Emission of GRB 100826A (2011)
  • Author(s): Yonetoku, Daisuke; Murakami, Toshio; Gunji, Shuichi; Mihara, Tatehiro; Toma, Kenji; Sakashita, Tomonori; Morihara, Yoshiyuki; Takahashi, Takuya; Toukairin, Noriyuki; Fujimoto, Hirofumi; Kodama, Yoshiki; Kubo, Shin; IKAROS Demonstration Team
  • Journal Title: Astropysical Journal Volume: 743 Pages: L30
  • Peer Reviewed
• [Journal Article] Gamma-Ray Burst Polarimeter - GAP - aboard the Small Solar Power Sail Demonstrator IKAROS (2011)
  • Author(s): Yonetoku, Daisuke; Murakami, Toshio; Gunji, Shuichi; Mihara, Tatehiro; Sakashita, Tomonori; Morihara, Yoshiyuki; Kikuchi Yukihiro; Takahashi, Takuya; Fujimoto, Hirofumi; Toukairin, Noriyuki; Kodama, Yoshiki; Kubo, Shin; and IKAROS Demonstration Team
  • Journal Title: PASJ Volume: Vol.63, No.3 Pages: 625-638
  • Peer Reviewed
• [Presentation] Study of emission mechanism of Gamma-Ray Bursts by the gamma-ray polarization with IKAROS-GAP (2012)
  • Author(s): D. Yonetoku
  • Organizer: 39th COSPAR
  • Place of Presentation: India
  • Year and Date: 20120714-22
• [Presentation] Study of prompt emission mechanism by the gamma-ray polarization with IKAROS-GAP (2012)
  • Author(s): D. Yonetoku
  • Organizer: Gamma-Ray Bursts in the Era of Rapid Follow-up
  • Place of Presentation: United Kingdom
  • Year and Date: 20120618-22
• [Presentation] Study of emission mechanism of Gamma-Ray Bursts by the gamma-ray polarization with IKAROS-GAP (2012)
  • Author(s): D. Yonetoku
  • Organizer: The Fermi/Swift GRB Conference 2012
  • Place of Presentation: Munich, Germany
  • Year and Date: 20120507-11
• [Presentation] 宇宙最大の爆発「ガンマ線バースト」はシンクロトロン放射起源か? (2012)
  • Author(s): 米徳大輔
  • Organizer: 日本天文学会秋季年会 2012年秋季年会企画セッション「次世代の多波長偏光サイエンス」
  • Place of Presentation: 大分大学(大分県)
  • Year and Date: 2012-09-19
• [Remarks]
  • URL: http://astro.s.kanazawa-u.ac.jp/~yonetoku/gap/index.htm
• [Remarks]
  • URL: http://www.kanazawa-u.ac.jp/university/administration/prstrategy/eacanthus/1212/07.html
• [Remarks]
  • URL: http://astro.s.kanazawa-u.ac.jp/~yonetoku/gap/asj-press/
• [Patent(Industrial Property Rights)] ガンマ線カメラ (2013)
  • Inventor(s): 米徳 大輔、若島 雄大、米持元(金沢大学)、根本 瀧男、久保 信、山口 明則、松浦 貢(クリアパルス株式会社)
  • Industrial Property Rights Holder: 根本 瀧男(クリアパルス株式会社)
  • Industrial Property Number: 特願2013-077555
  • Filing Date: 2013-04-03