Study on galactic origns of high energy cosmic rays

2015 Fiscal Year Final Research Report

• 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
• 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.

Free Research Field

宇宙線物理学