 |
| Titel |
Double discontinuities at the magnetotail plasma sheet-lobe boundary |
| VerfasserIn |
Y. C. Whang, D. Fairfield, R. P. Lepping, T. Mukai, Y. Saito, J. Slavin, A. Szabo |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 19, no. 9 ; Nr. 19, no. 9, S.1095-1105 |
| Datensatznummer |
250014319
|
| Publikation (Nr.) |
 copernicus.org/angeo-19-1095-2001.pdf |
|
|
|
|
|
| Zusammenfassung |
A double discontinuity is
a compound structure composed of a slow shock layer and an adjoining rotational
discontinuity layer on the postshock side. We use high-resolution data from
Geotail and Wind spacecraft to examine the interior structure within the finite
thickness of the discontinuity at the plasma sheet-lobe boundary and found that
recognizable MHD structures at the boundary can be stand-alone slow shocks or
double discontinuities. The plasma density increases significantly and the
magnetic field intensity decreases significantly across the interior of the
slow shock layer. Through the rotational layer, the magnetic field rotates
about the normal direction of the shock surface, as the plasma density and the
magnetic field intensity remain nearly unchanged. The rotational angle can vary
over a wide range. We notice that the observations of double discontinuities
are no less frequent than the observations of stand-alone slow shocks.
Identification of slow shocks and double discontinuities infers that plasma and
magnetic field lines continuously move across the boundary surface from the
lobe into the plasma sheet, and there is a conversion of magnetic field energy
into plasma thermal energy through the slow shock layer. The double
discontinuities also allows for a rapid rotation of the postshock magnetic
field lines immediately behind the shock layer to accommodate the environment
of the MHD flow in the plasma sheet region.
Key words. Magnetospheric physics
(plasma sheet) Space plasma physics (discontinuities; shock waves) |
| |
|
| Teil von |
|
|
|
|
|
|
|
|