摘要：We present an in situ evidence of electron beam-associated symmetric bipolar electrostatic solitary waves (ESWs) on the current sheet-side of the separatrix of the magnetic reconnection in the near-Earth magnetotail by multi-spacecraft observation of Cluster. Within one spin period, 42 cases of symmetric ESWs are continuously observed during 2 s by SC2 while other spacecrafts do not “detect” them. And the Plasma Electron and Current Experiment (PEACE) spinPAD mode data exhibits unidirectional electron beam antiparallel to the ambient field, and no electron beam-like distribution is found by other spacecrafts without ESW observation. Though the electron beam is strongly associated with the ESWs in observation by multiple spacecraft differentiation, however, the relationship between the counter-directed electron beam and the simultaneously observed ESWs remains unclear and open to the next study.
