The heavy nuclei of the primary cosmic radiation

The flux of primary cosmic-ray nuclei, heavier than protons, was determined at geomagnetic latitudes λ=55° and λ=30° °N. It is shown that at λ=30° at least one-half of the incident nucleons and a significant fraction of the incident cosmic-ray energy is due to the heavy component. The distribution of atomic numbers among the primaries was determined at both latitudes; the relative magnitude of the fluxes of the nuclei H:He:C,N,O: (nuclei of charge Z>10 is given approximately by the ratio 4000:1000:35:10. The possible significance of these results for the theories on the origin of cosmic rays is discussed.