New Solar Flare Particle Environment Models and Titan/Centaur INU Multiple-BitSingle Event Upset Rates

摘要

Recently-acquired solar flare data have been used to revise particle environmentmodels for the August 1972 and October 1989 events. The revised models are presented, together with their composite event model and the average flare model. These models are applied to calculate the rates of single and multiple bit single event upsets (SbSEUs and MbSEUs) during solar flares for the Titan/Centaur inertial navigation unit (INU) in an orbit of 26.6 deg inclination for a 6 hour geosynchronous orbit (GSO) transfer mission. Since shielding has been found to enhance immunity to solar flare SEU, the effect of the inherently present anisotropic shielding distributions was studied, including shielding by printed circuit board components.