Development of a wide field polarimeter for hard X-rays in small satellite

2015 Fiscal Year Final Research Report

• Project/Area Number: 25610042
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• 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): 2013-04-01 – 2016-03-31
• Keywords: 硬X線偏光測定 / ガンマ線バースト / 電子飛跡検出型コンプトンカメラ / 気球実験 / コンプトン散乱 / ガスTPC / 光電効果 / イメージング

Outline of Final Research Achievements

Ｗe have developed Electron Tracking Compton Camera for exploring MeV gamma astronomy, which have a capability of high quality imaging with a wide Field of View of 4str and strong background rejection. Thus, ETCC is considered to be a good detector for the detection of GRBs. Also, since Compton scattering keeps a polarization of gamma very well, ETCC would be a good polarization-measured instrument having an imaging ability. After checking the good modulation factor of ETCC for above 100 keV by simulation, we have examined the modulation factor of ETCC at Synchrotron Facility in Japan and obtained a good modulation factor of ~0.6 at 130keV which is one of best results for hard X-ray polarization detector. Furthermore, we succeeded to measure the polarization using a weak RI source by applying an imaging cut for the background suppression. This is a first result in the world of imaging polarimeter for hard X-rays and nuclear gammas.

Free Research Field

宇宙線物理学