Precise measurement of cosmic-ray proton and helium spectra with the BEES spectrometer

T. Sanuki, M. Motoki, H. Matsumoto, E. S. Seo, J. Z. Wang, K. Abe, K. Anraku, Yoichi Asaoka, M. Fujikawa, M. Imori, T. Maeno, Y. Makida, N. Matsui, H. Matsunaga, J. Mitchell, T. Mitsui, A. Moiseev, J. Nishimura, M. Nozaki, S. OritoJ. Ormes, T. Saeki, M. Sasaki, Y. Shikaze, T. Sonoda, R. Streitmatter, J. Suzuki, K. Tanaka, I. Ueda, N. Yajima, T. Yamagami, A. Yamamoto, T. Yoshida, K. Yoshimura

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291 Citations (Scopus)


We report cosmic-ray proton and helium spectra in energy ranges of 1-120 GeV nucleon-1 and 1-54 GeV nucleon-1, respectively, measured by a flight of the Balloon-borne Experiment with Superconducting Spectrometer (BESS) in 1998. The magnetic rigidity of the cosmic ray was reliably determined by highly precise measurement of the circular track in a uniform solenoidal magnetic field of 1 T. Those spectra were determined within overall uncertainties of ±5% for protons and ±10% for helium nuclei including statistical and systematic errors.

Original languageEnglish
Pages (from-to)1135-1142
Number of pages8
JournalAstrophysical Journal
Issue number2 PART 1
Publication statusPublished - 2000 Dec 20
Externally publishedYes



  • Cosmic rays
  • Elementary particles

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Sanuki, T., Motoki, M., Matsumoto, H., Seo, E. S., Wang, J. Z., Abe, K., Anraku, K., Asaoka, Y., Fujikawa, M., Imori, M., Maeno, T., Makida, Y., Matsui, N., Matsunaga, H., Mitchell, J., Mitsui, T., Moiseev, A., Nishimura, J., Nozaki, M., ... Yoshimura, K. (2000). Precise measurement of cosmic-ray proton and helium spectra with the BEES spectrometer. Astrophysical Journal, 545(2 PART 1), 1135-1142.