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Measurements of Cosmic-ray Low-energy Antiproton and Proton Spectra in a Transient Period of the Solar Field Reversal

Y. Asaoka·Y. Shikaze·K. Abe·K. Anraku·M. Fujikawa·H. Fuke·S. Haino·M. Imori·K. Izumi·T. Maeno·Y. Makida·S. Matsuda·N. Matsui·T. Matsukawa·H. Matsumoto·H. Matsunaga·J. Mitchell·T. Mitsui·A. Moiseev·M. Motoki·J. Nishimura·M. Nozaki·S. Orito·J. F. Ormes·T. Saeki·T. Sanuki·M. Sasaki·E. S. Seo·T. Sonoda·R. Streitmatter·J. Suzuki·K. Tanaka·K. Tanizaki·I. Ueda·J. Z. Wang·Y. Yajima·Y. Yamagami·A. Yamamoto·Y. Yamamoto·K. Yamato·T. Yoshida·K. Yoshimura
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Abstract

The energy spectra of cosmic-ray low-energy antiprotons and protons have been measured by BESS in 1999 and 2000, during a period covering the solar magnetic field reversal. Based on these measurements, a sudden increase of the antiproton to proton flux ratio following the solar magnetic field reversal was observed, and it generally agrees with a drift model of the solar modulation.

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Y. Asaoka, Y. Shikaze, K. Abe, K. Anraku, M. Fujikawa, H. Fuke, S. Haino, M. Imori, K. Izumi, T. Maeno, Y. Makida, S. Matsuda, N. Matsui, T. Matsukawa, H. Matsumoto, H. Matsunaga, J. Mitchell, T. Mitsui, A. Moiseev, M. Motoki, J. Nishimura, M. Nozaki, S. Orito, J. F. Ormes, T. Saeki, T. Sanuki, M. Sasaki, E. S. Seo, T. Sonoda, R. Streitmatter, J. Suzuki, K. Tanaka, K. Tanizaki, I. Ueda, J. Z. Wang, Y. Yajima, Y. Yamagami, A. Yamamoto, Y. Yamamoto, K. Yamato, T. Yoshida, K. Yoshimura. 2002-01-25. Measurements of Cosmic-ray Low-energy Antiproton and Proton Spectra in a Transient Period of the Solar Field Reversal. https://doi.org/10.1103/physrevlett.88.051101

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