RELATIVE ENERGY SPECTRA OF CARBON AND OXYGEN NUCLEI IN PRIMARY COSMIC RADIATION

Measurements of the energy spectra of carbon and oxygen nuclei in the primary cosmic radiation over the energy range from 140 MeV/nuc to 30 BeV/nuc are reported. An average C/O ratio of 1.11±0.02 is obtained at the top of the atmosphere. This ratio is found to be constant to within ∼5% over the entire energy range. The energy spectra of these two nuclei are presented and compared with earlier measurements and with satellite observations at low energies. After correction for propagational effects in 4 g/cm2 of interstellar hydrogen the 'source' C/O ratio is found to be ∼0.9. The astrophysical implications of this C/O ratio are discussed. © 1969 D. Reidel Publishing Company.