Flux transfer events simultaneously observed by Polar and Cluster: Flux rope in the subsolar region and flux tube addition to the polar cusp

摘要: [1] In this paper we present observational evidence of a flux transfer event observed simultaneously at low-latitude by Polar and high-latitude Cluster. This occurs on 21 March 2002, when both Cluster are located near local noon but with large latitudinal separation. During the event, is moving outbound from polar cusp to magnetosheath in equatorial magnetopause. The observations show that between equator northern cusp. observe FTE's two open tubes: encounters southward tube northward high latitude. FTE appears be rope helical magnetic field lines as it has strong core component boundary normal direction exhibits bipolar variation. Unlike FTE, does not exhibit characteristic perturbation field. However, plasma data clearly reveal its configuration. It shows have straightened inside become more aligned neighboring tubes moves Enhanced electrostatic fluctuations been within core, low latitudes. provides unique opportunity understand signatures nature time-varying reconnection. existing models cannot accommodate all features global observations, coordinated measurements largely spaced multiple spacecraft place important constraints which crucial development refinement models.