Method of cosmogonic nuclides as an inderect approach of cosmic ray investigations

The results of theoretical and experimental investigations of production of cosmic origin nuclides in the Moon ground with the aim of obtaining information on the intensity of cosmic rays (CR) in the past and the estimation of possible durable CR variations, are discussed. The Ridi and Arnold model has been used to calculate velocities of production of cosmic origin 26Al and 53Mn nuclides in the upper layers (up to 5gxcm-2) of the Moon rocks by solar CR, and compared with the data of the experiment. Effects connected with the production of cosmic origin 26Al and 53Mn nuclides with galactic cosmic rays are studied in the Moon ground at the depths higher than 5gxcm-2. The data obtained show that the medium flux of solar CR during 1-10 million years was 90 protonxcm-2xs-1 with the energy above 10 MeV and the characteristic rigidity of 100 MV. This result proves the constancy of solar cosmic ray intensity for the last 100 million years. The medium flux of galactic CR for the last 2 million years was 0.13 protonxcm-2xs-1sr-1 with the energy above 1 GeV, which agrees with the modern medium modulated flux behind the solar cycle