TITLE:
About the Energy Interval beyond the Ankle Where the Cosmic Radiation Consists Only of Ultraheavy Nuclei from Zinc to the Actinides
AUTHORS:
Antonio Codino
KEYWORDS:
Ultrahigh Energy Cosmic Ray, Chemical Composition, GZK Effect
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.5 No.1,
January
31,
2017
ABSTRACT:
According to recent measurements the tendency of the chemical composition above the ankle is characterized by increasing fractions of intermediate and heavy nuclei and a dominance of light nuclei around the ankle. Calculation of the chemical composition in the range 3.5 × 1018 - 5 × 1019 eV according to new principles explains both the rising tendency of the heavy component. The calculation is prolonged to the adjacent interval 5 × 1019- 2.4 × 1021 eV using the same theoretical background and some features of the observed cosmic-ray spectrum. It results that above the energy of 6.7 × 1020 eV, where the flux is estimated to be 1.8 × 10?30 particles/m2 s sr GeV, the cosmic radiation consists only of nuclei heavier than Zinc. Measurements of the spectrum of present and past experiments are compared with the calculations.