Observation of Galactic Gamma-ray Sources using Electron Tracking Compton Camera with Balloon borne Experiment

2014 Fiscal Year Final Research Report

• Project/Area Number: 21224005
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Kyoto University
• Principal Investigator: TANIMORI Toru 京都大学, 理学(系)研究科(研究院), 教授 (10179856)
• Co-Investigator(Renkei-kenkyūsha): KUBO Hidetoshi 京都大学, 大学院理学研究科, 准教授 (40300868) ; TAKADA Atsushi 京都大学, 大学院理学研究科, 助教 (90531468)
• Project Period (FY): 2009-04-01 – 2015-03-31
• Keywords: MeVγ線天文学 / コンプトンカメラ / 高エネルギー天体 / 超新星 / 元素合成 / GRB / TPC / MPGD

Outline of Final Research Achievements

For　MeV gamma-ray astronomy, we developed Electron　Tracking Compton Camera (ETCC) consisting of TPC and scintillators. By measuring electron tracks, ETCC measures the direction of gamma-rays as a small arc, which provides good background rejection by the dE/dx, and clear imaging. Here a 30cm-cube-ETCC was developed to catch gammas from Crab in SMILE-II balloon with >5σ for 4 hrs in 2013. SMILE-II was irradiated by intense gammas and neutron by 140MeV proton, and measured clear image of a weak RI without the efficiency deterioration under 10 times stronger radiation than space by removing most background by dE/dx. Finally its sensitivity was improved to 8-10σ by attaining the angular resolution of the track to that determined by multiple scattering. Thus we show the ability of ETCC to give a 10 times better significance than standard CCs with a same detection area by ETCC. Based on this technology, 4 modules of 50cm-cube ETCCs in space is expected to exceed over 1mCrab.

Free Research Field

宇宙線物理学