O+ observations in the cusp: Implications for dayside magnetic field topology

摘要: Under conditions of sustained northward interplanetary magnetic field (IMF), magnetospheric lines on the dayside may undergo multiple reconnection, producing closed flux tubes filled with solar wind plasma. Ionospheric O + beams energies ∼1 keV/e that are propagating parallel to in northern cusp region potential evidence for this reconnection process. Using observations from Polar spacecraft, we present cusp. A statistical study these events indicates they very rare data. Therefore, under assumption occurrence frequency IMF appears be small. Thus process is insufficient account nearly continuous population plasma magnetosphere.