10:30 AM - 10:45 AM
[PEM09-21] Tailward leap of magnetic reconnection: A THEMIS case study
Keywords:magnetotail, magnetic reconnection, substorm, auroral breakup
Another auroral breakup occurred 12 min further later at a latitude higher than the previous breakup. At the same time a change of the flow direction from tailward flow to earthward flow was observed by the THEMIS-1 satellite. This flow reversal is often interpreted as the tailward retreat of a single magnetic reconnection site. However, another THEMIS satellite located 5 Re earthward from THEMIS-1 observed the earthward flow 1 min later. Thus, the observed sequence rather corresponds to a tailward leap of the reconnection site. We suggest that the poleward leap of auroral breakup is associated with the tailward leap of reconnection site as a consequence of the magnetic flux pileup in the dipolarization region.