Problem of the energy spectrum of ultrahigh-energy cosmic rays

A number of cosmic-ray energy spectra measured in the energy region E ₀ ≥ 10¹⁷ eV at the Yakutsk array and at AGASA, Haverah Park, HiRes, Auger, and SUGAR within different periods of time were considered. It was shown that, upon rescaling the energy of these spectra by factors of K = 0.75, 0.85, 0.9, 1.02, 1.19, and 1.29, respectively, all of them agree with one another rather well in shape. The factors K themselves exhibit a pronounced north-south dependence on the geographical latitude of the positions of the above arrays.