Fig. 7.—

Absolute differential energy spectra of primary protons and helium nuclei at TOA multiplied by $E_K^{2.7}$ measured by BESS-Polar I and BESS-Polar II. Spectra reported by BESS98 (Sanuki et al. 2000), BESS-TeV (Haino et al. 2004a), ATIC-2 (Panov et al. 2007), PAMELA (Adriani et al. 2011, 2014), and AMS-02 (Aguilar et al. 2015a,b) are shown for comparison. Differences in the BESS-Polar I and BESS-Polar II spectra at low energies are due to solar modulation.