Magnetospheric flux erosion events are flux transfer events

Abstract

Recent results have shown that magnetic reconnection at the Earth's dayside magnetopause manifests itself most frequently as an impulsive process. Haerendel et al.1, using data from the HEOS 2 spacecraft, were the first to notice short time scale magnetic field perturbations inside the magnetopause, which they interpreted as flux erosion events resulting from transient reconnection in the polar cusp regions. Using higher time resolution data from the ISEE 1 and 2 satellite pair, Russell and Elphic2 subsequently discovered certain characteristic magnetic field signatures in the magnetosheath, which they termed flux transfer events (FTEs). They also interpreted these events in terms of transient, localized reconnection. It has often been suggested3–7 that Haerendel et al.'s flux erosion events and Russell and Elphic's FTEs have a close physical connection, but proof of this has so far been lacking. Here we show that flux erosion events and flux transfer events are indeed the same physical phenomenon.