Study on galactic origns of high energy cosmic rays

• Project/Area Number: 23403002
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: KAKIMOTO Fumio 東京工業大学, 理工学研究科, 教授 (00092544)
• Co-Investigator(Renkei-kenkyūsha): TSUNESADA Yoshiki 大阪市立大学, 大学院理学研究科, 准教授 (50401526)
• Project Period (FY): 2011-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥19,370,000 (Direct Cost: ¥14,900,000、Indirect Cost: ¥4,470,000); Fiscal Year 2015: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000); Fiscal Year 2014: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2013: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2012: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000); Fiscal Year 2011: ¥7,670,000 (Direct Cost: ¥5,900,000、Indirect Cost: ¥1,770,000)
• Keywords: 宇宙線 / 空気シャワー / 宇宙線起源 / 質量組成 / 縦方向発達 / 空気チェレンコフ光

Outline of Final Research Achievements

We observe the energy spectrum and the mass composition of primary cosmic rays and then establish the energy region where the origins of primary cosmic rays change from galactic to extra galactic ones. Observed energy spectrum are well fitted with a power law function of primary energies with a change of the power index at 10＾15.6 eV. Moreover, preliminary results for the mass composition show that major component of primary cosmic rays is gradually lighter as primary energies from iron at 10＾16 eV.

Research Products

• [Int'l Joint Research] 国立サンアンドレス大学(ボリビア)
• [Journal Article] New air Cherenkov light detectors to study mass composition of cosmic rays with energies above knee region (2014)
  • Author(s): Y. Tsunesada et al.
  • Journal Title: Nuclear Instruments and Methods in Physics Research A Volume: 763 Pages: 320-328
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] 高山での空気チェレンコフ光観測によるKnee領域以上の宇宙線核組成研究Ⅳ (2015)
  • Author(s): 勝谷龍一
  • Organizer: 日本物理学会
  • Place of Presentation: 早稲田大学早稲田キャンパス
  • Year and Date: 2015-03-21
• [Presentation] 高山での空気チェレンコフ光観測によるKnee領域以上の宇宙線核組成研究Ⅲ (2014)
  • Author(s): 勝谷龍一
  • Organizer: 日本物理学会
  • Place of Presentation: 佐賀大学本庄キャンパス
  • Year and Date: 2014-09-20
• [Presentation] 高山での空気チェレンコフ光観測によるKnee領域以上の宇宙線核組成研究II (2014)
  • Author(s): 常定芳基
  • Organizer: 日本物理学会
  • Place of Presentation: 東海大学湘南キャンパス
• [Presentation] 高山での空気チェレンコフ光観測によるKnee領域以上の宇宙線核組成研究 (2012)
  • Author(s): 勝谷龍一
  • Organizer: 日本物理学会
  • Place of Presentation: 関西学院大学
  • Year and Date: 2012-03-24
• [Remarks]
  • URL: http://wwwcr.phys.titech.ac.jp/