Electron structures in the cusp/cleft region observed by DE 2 satellite

摘要: Narrow enhancements of electron precipitation, with energy and flux well above typical values, have been observed DE 2 in the cusp/cleft region. The range 0.2-1 keV was orders magnitude higher these structures than magnetosheath were seen approximately 80% cusp crossings at ionospheric altitudes. Typically, there more one structure each crossing. position showed a systematic variation: for poleward ion dispersion (energy decreases increasing latitude), often on equatorial boundary cusp, while equatorward decreasing boundary. This suggests that are associated newly reconnected field lines. spectra suggest field-aligned acceleration processes could produce structures, first near during reconnection lines then motion tubes through polar ionosphere.