Plasma injection events at synchronous orbit related to positive Dst

AST 6 spacecraft synchronous orbit measurements are compared with space and ground data in a study of plasma effects related to SI and SC magnetic perturbations. It is found that synchronous orbit plasma injections related to the sudden phenomena are similar to those associated with substorms, although the former occur at all local times. The synchronous orbit plasma injections are interpreted as the co-location of particle boundaries on an inward propagating front and the compression magnetic pulse associated with SI and SC events is seen as responsible for the co-location of the boundaries and their inward propagation. The positive Dst magnetic pulse plays a role similar to that of the magnetic tail reconfiguration pulse associated with substorms, and evidence is shown that positive Dst enhances magnetospheric convection independently of interplanetary magnetic field direction