A Study of the Effect of Geomagnetically Trapped Radiation on Unprotected Solar Cells

The problem of solar cell damage by proton and electron radiation is treated analytically from a theoretical and empirical viewpoint. The general approach is to form a damage integral, consisting of the integral over the energy spectrum, for both electrons and protons, of an integrand formed by the product of the differential energy spectrum and a damage function, and to relate this damage integral to the deterioration of solar cells under irradiation. The damage function is considered theoretically from the microscopic viewpoint of collision theory and empirically by using available experimental data. By making several approximations and assumptions, the data from the solar cell patches on Explorer XI is compared with predictions based upon the empirical relationship developed for the damage integral.