 |
| Titel |
Asymmetry in the magnetic field signatures of flux transfer events |
| VerfasserIn |
Robert Fear, Steve Milan, Joachim Raeder, David Sibeck |
| Konferenz |
EGU General Assembly 2010
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250033814
|
|
|
|
|
|
| Zusammenfassung |
| Flux transfer events (FTEs) are bursts of magnetic reconnection at a planetary magnetopause
and have been observed at Earth, Jupiter and Mercury. They are usually identified by their
bipolar signatures in the component of the magnetic field normal to the magnetopause (BN).
Several conceptual models have been proposed for FTE formation, including models
based on reconnection at a single reconnection line (X-line) and at multiple X-lines.
Two-dimensional magnetohydrodynamic models have previously been used to simulate both
scenarios and have found a tendency for FTEs generated by single X-line reconnection to
exhibit an asymmetry in the BN signature, with the leading peak being substantially smaller
in magnitude than the trailing peak. On the other hand, FTEs generated by multiple X-line
reconnection led to more symmetric signatures. We present a comparison of these
simulation results with observations made at the Earth’s magnetopause by the Cluster
spacecraft, using a dataset of 213 FTEs which were observed by all four spacecraft
in 2002/3. A tendency is found for the BN signatures to be asymmetric, but with
the leading peak stronger than the trailing peak - opposite to the prediction made
by the 2D models. We also compare the observations with the results of a more
recent global MHD simulation and find similar trends to those observed by Cluster. |
|
|
|
|
|
|