Kanagawa University Faculty of Engineering
Aoyama Gakuin University College of Science and Engineering
Kanagawa University of Human Services
Japan Aerospace Exploration Agency Institute of Space and Astronautical Science
出版者
宇宙航空研究開発機構
出版者（英）
Japan Aerospace Exploration Agency (JAXA)
雑誌名
宇宙航空研究開発機構研究開発報告: 大気球研究報告
雑誌名(英)
JAXA Research and Development Report: Research Reports on High Altitude Balloons
Primary cosmic-ray proton spectrum is one of the most important quantities to interpret cosmic-ray phenomena inside the atmosphere. Recently proton measurements are attracted more attentions to estimate the absolute flux of atmospheric neutrinos which is important to make more precise analysis of the neutrino oscillations being performed with Super-Kamiokande. Similar attention is also paid to the observations of the absolute flux of muons which are the partners of neutrinos. Atmospheric gamma-ray spectra from 30 GeV to 10 TeV have been observed with total exposure of 6.46 m(sup 2) sr day using emulsion chambers at balloon altitude. Atmospheric gamma rays at high altitude of several g/cm(sup 2) are almost produced by a single interaction of primary cosmic rays, and useful to estimate the primary proton flux and to interpret the various cosmic-ray phenomena inside the atmosphere. Using the atmospheric gamma-ray spectra, primary proton spectrum in the energy range of 300 GeV to 30 TeV was deduced, assuming an appropriate hadronic interaction model. This spectrum fills a gap in the currently observed proton spectra. Since charged pions are produced almost two times of neutral pions, the muon flux can also be deduced at high altitude from the gamma-ray spectra without referring to the primary cosmic-ray flux or hadronic interaction models. The muon spectrum deduced by taking into account of the effect of decay of muon and K meson is presented, and it is compared with the observed data.
大気ガンマ線から推定した1次陽子及び上空のミューオンスペクトル
46714003.pdf
(1.03MB)
