Radiation measurements on the ''Kosmos-900'' satellite

Presented are the experiment description and preliminary results of measuring the differential proton spectra in the energy range from 30 keV up to 30 MeV in the Earth radiation belts performed on the ''Kosmos-900'' satellite. According to the data obtained in the morning sector of magnetosphere a comparative analysis of differential proton spectra is carried out in the magnetically calm period of large duration and during magnetic agitation. In the range of Mc Ilvine parameter L approximately 3-5 differential proton spectra have maximum at the energy Ep approximately 100-300 keV. Maximum values Esub(max)(L) are higher in magnetically calm period than during magnetic agitation. This difference increases at L decrease, reaches the largest value on L=4 and decreases at further decrease of α. In the depth of plasmosphere (L approximately 3). Esub(max)(L) positions coincide in magnetically calm period and during magnetic agitation. A relation between Esub(max)(L) position in differential proton spectra and the average space distribution of cold plasma is traced