High energy electron observation by Polar Patrol Balloon flight in Antarctica

• Main Authors: Shoji Torii, Tadahisa Tamura, Kenji Yoshida, Hisashi Kitamura, Takamasa Yamagami, Hiroyuki Murakami, Nobuhito Tateyama, Jun Nishimura, Yoshitaka Saito, Shigeo Ohta, Michiyoshi Namiki, Yukihiko Matsuzaka, Issei Iijima, Masaki Ejiri, Hisao Yamagishi, Akira Kadokura, Makio Shibata, Yusaku Katayose, Katsuaki Kasahara, Kohei Mizutani, Tadashi Kobayashi, Yoshiko Komori, Toshinori Yuda, Jin Chang
• Format: Report
• Language: English
• Published: Advanced Research Institute for Science and Engineering, Waseda University/Faculty of Engineering, Kanagawa University/Faculty of Engineering, Kanagawa University/National Institute of Radiological Sciences/ISAS-JAXA/Department of Physics, Rikkyo University/Faculty of Engineering, Kanagawa University/ISAS-JAXA/ISAS-JAXA/ISAS-JAXA/ISAS-JAXA/ISAS-JAXA/ISAS-JAXA/National Institute of Polar Research/National Institute of Polar Research/National Institute of Polar Research/Department of Physics, Yokohama National University/Department of Physics, Yokohama National University/Department of Information Science and Engineering, Shibaura Institute of Technology/Department of Physics, Saitama University/Department of Physics, Aoyamagakuin University/Kanagawa University of Human Services/Institute for Cosmic Ray Research, University of Tokyo/Purple Mountain Observatory, Chinese Academy of Science 2006
• Subjects: cosmic ray; high energy electron; balloon observation; Antarctica; Antarc*; Advances in polar upper atmosphere research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=6421; http://id.nii.ac.jp/1291/00006421/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=6421&item_no=1&attribute_id=18&file_no=1

We accomplished a balloon observation of the high-energy cosmic-ray electrons in 10-1000GeV to reveal the origin and the acceleration mechanism. The observation was carried out for 13 days at an average altitude of 35km by the Polar Patrol Balloon (PPB) around Antarctica in January 2004. The detector is an imaging calorimeter composed of scintillating-fiber belts and plastic scintillation counters sandwiched between lead plates. The geometrical factor is about 600cm^2sr, and the total thickness of lead absorber is 9 radiation lengths. The performance of the detector has been confirmed by a test flight at the Sanriku Balloon Center and by an accelerator beam test using the CERN-SPS (Super Proton Synchrotron at CERN). The new telemetry system using the Iridium satellite, the power system supplied by solar panels and the automatic flight level control operated successfully during the flight. We collected 5.7×10^3 events over 100GeV, and selected the electron candidates by a preliminary data analysis of the shower images. We report here an outline of both detector and observation, and the first result of the electron energy spectrum over 100GeV obtained by an electronic counter.