Precharging Effects on the SGEMP Response

Spacecraft charging arising from natural environments is examined in terms of effects on the system-generated electromagnetic (SGEMP) response. The gross external response of a satellite body is modeled using a cylindrical object initially charged to different voltages and subjected to a variety of photon environments. Charging of the body as a whole is briefly compared to the response produced by charging of different parts with respect to each other. Negative charging of the total body can enhance peak replacement currents by up to a factor of two. Differential charging perturbations of the same order and higher have also been computed.