Three‐dimensional magnetic flux rope structure formed by multiple sequential X‐line reconnection at the magnetopause

Abstract

Time History of Events and Macroscale Interactions duringSubstorms spacecraft observed a flux transfer event (FTE) on the dayside magnetopause, which has been previously proved to be generated by multiple, sequential X-line reconnection (MSXR) in a 2-D context. This paper reports a further study of the MSXR event to show the 3-D viewpoint based on additional measurements. The 3-D structure of the FTE flux rope across the magnetospheric boundary is obtained on the basis of multipoint measurements taken on both sides of the magnetopause. The flux rope's azimuthally extended section is found to lie approximately on the magnetopause surface and parallel to the X-line direction; while the axis of the magnetospheric branch is essentially along the local unperturbed magnetospheric field lines. In the central region of the flux rope, as distinct from the traditional viewpoint, we find from the electron distributions that two types of magnetic field topology coexist: opened magnetic field lines connecting the magnetosphere and the magnetosheath and closed field lines connecting the Southern and Northern hemispheres. We confirm, therefore, for the first time, the characteristic feature of the 3-D reconnected magnetic flux rope, formed through MSXR, through a determination of the field topology and the plasma distributions within the flux rope. Knowledge of the complex geometry of FTE flux ropes will improve our understanding of solar wind-magnetosphere interaction.Citation: Zhong, J., et al. (2013), Three-dimensional magnetic flux rope structure formed by multiple sequential X-line reconnection at the magnetopause,

Decay of mesoscale flux transfer events during quasi‐continuous spatially extended reconnection at the magnetopause

“…[] and Zhong et al . [], and to study microphysical processes that may play a role in the FTE evolution and transport. Such processes include reconnection at the center of FTE flux ropes, which Øieroset et al .…”

A sequence of flux transfer events potentially generated by different generation mechanisms

“…Instead, in the original Russell and Elphic [] model a poleward acceleration of the plasma could be detected inside the FTE, but the velocity increase should be observed during the entire FTE and not only at its trailing edge [ Sonnerup , ]. In the multiple X line model [ Lee and Fu , ], two converging reconnection jets at the borders of the FTE are expected if the FTEs are observed during their formation [ Hasegawa et al , ; Trenchi et al , ; Øieroset et al , ; Zhang et al , ; Zhong et al , ; Pu et al , ]. The lack of the southward reconnection jets at the leading edge of the FTEs could be explained possibly also in the context of multiple X line reconnection, if reconnection at the southern X line is more active and reconnection at the northern X line is not active when the FTEs are detected.…”

Magnetic Reconnection at a Thin Current Sheet Separating Two Interlaced Flux Tubes at the Earth's Magnetopause

“…Aside from large‐scale FTEs often observed at the magnetopause, small‐scale perturbations with magnetic signatures akin to those of FTEs might indicate the existence of very localized magnetic island structures (Hesse et al, ). Such magnetic islands may also be generated by multiple X‐line reconnection (Pu et al, ; Zhong et al, ) (i.e., between two X‐lines created sequentially on the magnetopause) or at a single X‐line owing to rapid variations of the reconnection rate (Huang et al, ). Their typical signatures are an enhancement of the total magnetic field strength and a magnetic bipolar signature (Teh et al, ).…”