Successive Measurements of Cosmic-Ray Antiproton Spectrum in a Positive Phase of the Solar Cycle
نویسندگان
چکیده
The energy spectrum of cosmic-ray antiprotons (p̄’s) has been measured by BESS successively in 1993, 1995, 1997 and 1998. In total, 848 p̄’s were clearly identified in energy range 0.18 to 4.20 GeV. From these successive measurements of the p̄ spectrum at various solar activity, we discuss about the effect of the solar modulation and the origin of cosmic-ray p̄’s. Measured p̄/p ratios were nearly identical during this perfiod, and were consistent with a prediction taking the charge dependent solar modulation into account. PACS: 98.70.Sa, 95.85.Ry
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