Fraction of protons in primary cosmic rays according to data from the PAMIR experiment in consideration of the response of X-ray emulsion chambers

Adjusted data on the fraction of protons in the mass composition of primary cosmic rays (PCRs) in the energy range of 1015–1017 eV are presented. Adjustments are made according to detailed calculations of the response of the X-ray emulsion chamber in the PAMIR experiment. It is demonstrated that the fraction of protons in a PCR is 16–18% for E 0 ≈ 1015–1016 eV and does not change within the error for E 0 ≈ 1016–1017 eV.