Structure and Origin of Magnetic Flux Transport Bursts in the Magnetotail

Abstract:

In situ observations have suggested that magnetic flux
transport in the magnetotail is impulsive with typical pulse duration of 10 to
100 seconds. Multi-point observations, that will be reviewed in this paper,
also have revealed that the flux transport pulses are spatial structures moving
at a velocity of 100 to 500 km/s. That corresponds to a spatial scale of the
pulses of 2 to 5 Earth's radii (RE). It has been established that the flux
transport is localized in cross-tail direction within a 1 to 3 RE-wide channels
and dominantly observed in the premidnight magnetotail sector. A concept of
impulsive (time-dependent) magnetic reconnection may explain the short-time flux
transfer pulses. It is unknown, however, what determines the characteristic time
scale of the pulses and spatial localization of the flux transport channels. A
role of Rayleigh-Taylor-type and drift instabilities in structuring and
localization of the flux bursts is another open question.