11:40 AM - 11:55 AM
[PEM13-20] Substorm -like energetic electron injection observed at the plasma sheet boundary in the inner magnetosphere
Keywords:plasma sheet boundary, electron acceleration
However, the observed energetic electron bursts look quite similar to typical dispersionless substorm injection events. If the observed electron bursts are due to the substorm injection, the observation cannot be explained by the standard understanding of the injection because (1) the injection occurs associated with local magnetic field dipolarizations in downstream of the magnetotail reconnection jets (in deep inside of the plasma sheet) and (2) energetic electrons observed at the plasma sheet boundary are thought to be directly accelerated from magnetotail reconnection sites. Since the pitch angle distribution of 100-200 keV electron shows enhancement both of parallel and perpendicular fluxes, the observed results suggest the coexistence of (1) and (2). In this presentation, we will discuss the physical meanings of the observed electron bursts. The discussion is important to address the relationship between magnetotail reconnection and injections, and the results might contribute to a better understanding of electron acceleration processes and energy input to the inner magnetosphere.