Plasma sheet instability related to the westward traveling surge

摘要: The detailed analysis of an isolated dispersionless substorm is performed on the basis field and particle data collected in situ by geostationary satellite GEOS 2 from ground-based instruments installed close to magnetic footprint. These give evidence for (1) quasi-periodic variations configuration, which alternatively taillike dipolelike, (2) in-phase oscillations flux energetic electrons, high when configuration dipolelike vice versa, (3) a gradient ions, is, average, earthward but undergoes large fluctuations around this average direction, (4) transient quasi-dc electric field, reverses its direction eastward westward. It shown that these results are consistent with development instability leads westward propagating “wave”. source differential drift electrons ions highly stressed (in β plasma). Evidence given system localized field-aligned currents flowing alternately equatorward at leading trailing edges wave. This current resulting temporal produces so-called Pi pulsations, ionospheric level. closure equatorial region antiparallel tail current, therefore reduction or cancellation. reduction/cancellation restores dipole (dipolarization) generates directed induced (injection). Hence, dipolarization injection consequences instability. Finally, it suggested traveling surge observed simultaneously all-sky cameras, 2, image transmitted upper atmosphere precipitating electrons.