Relationship between the values of proton fluxes outside the Earth’s magnetosphere and solar activity

The necessity for long-term forecast of proton fluxes in near-Earth space is explained by the need to ensure the safety of space missions. In the article the data on proton fluxes outside the Earth's magnetosphere for 1972-2018, obtained on board IMP and GOES series is analyzed. The dependences of the average annual proton fluxes (for energies > 1 MeV, > 2 MeV, > 4 MeV, > 10 MeV, > 30 MeV, > 60 MeV) and their standard deviations from the Wolf numbers were revealed, and the pattern of distribution of proton fluxes was derived. The constructed probability distribution functions of the average annual proton fluxes for given values of the Wolf numbers allow us to estimate the probability that the average annual value of proton fluxes will not exceed a certain value for integer Wolf number.