Reference : Observations of significant flux closure by dual lobe reconnection
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Earth sciences & physical geography
Physical, chemical, mathematical & earth Sciences : Multidisciplinary, general & others
Observations of significant flux closure by dual lobe reconnection
Imber, S. M. [> > > >]
Milan, S. E. [> > > >]
Hubert, Benoît mailto [Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP) >]
Annales Geophysicae
Copernicus Publications
Yes (verified by ORBi)
[en] magnetospheric physics ; magnetospheric configuration and dynamics ; plasma convection ; solar windmagnetosphere interactions
[en] We present an interval of dual lobe reconnection during which interplanetary magnetic field lines are captured by the magnetosphere by reconnecting at high latitudes in both the Northern and the Southern Hemispheres. This event was identified using measurements of the ionospheric convection flow and observations of the aurora using the Super-DARN radars and the IMAGE spacecraft. A cusp spot, characteristic of northward IMF, is clearly visible for a 30 min period enabling the ionospheric footprint of the Northern Hemisphere merging gap to be accurately determined. During the interval a strong burst of sunward flow across the dayside open/closed field line boundary (OCB) is observed, which we interpret as the reconfiguration of the magnetosphere following a burst of reconnection. Noon-midnight and dawn-dusk keograms of the aurora show that the polar cap shrinks during the interval indicating that a large amount of flux was closed by the reconnection. Using the SuperDARN potential maps it is possible to calculate that the amount of flux closed during the interval is 0.13 GWb which represents approximately 10% of the pre-existing polar cap. The number of ions captured by the burst of dual lobe reconnection was calculated to be similar to 2.2x10(31), more than sufficient to populate a cold, dense plasma sheet. That a dense plasma sheet was not subsequently observed is discussed in terms of subsequent changes in the IMF.
Researchers ; Professionals

File(s) associated to this reference

Fulltext file(s):

Restricted access
Imber_angeo-25-1617-2007.pdfPublisher postprint1.18 MBRequest copy

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.