Proton Upsets in Orbit

This paper presents a method of predicting proton-induced single event upset rates in spacecraft RAMs. The approach uses a sensitivity parameter A, determined from one or more experimental measurements of upset cross sections made at any proton energy above threshold. Parameter A uniquely determines a curve for the energy dependence of the upset cross section. This curve can be combined with the proton spectrum at the RAM to predict its upset rate. Predicted upset rates for 600 circular orbits are presented.