A mechanism for the multiple brightenings of dayside poleward‐moving auroral forms

Magnetic reconnection plays an important role in the magnetosphere‐ionosphere coupling and may lead to the formation of the dayside auroras. Observations of the dayside auroras may provide clues to the reconnection process at the magnetopause. Recently Fasel et al. [1992] observed poleward‐moving dayside auroral forms that rebrighten during their lifetimes. Lee et. al. [1993] examined the topology of magnetic flux ropes formed by the patchy multiple X‐line reconnection (PMXR), in which a magnetic flux tube reconnects with other flux tubes at multiple sites of limited extent. This paper develops the connection between the evolution of the magnetic flux ropes and the multiple brightenings of poleward‐moving dayside auroral forms.