Pc5 pulsations and their possible source mechanisms: a case study
Item
Title (Dublin Core)
en-US
Pc5 pulsations and their possible source mechanisms: a case study
Description (Dublin Core)
en-US
During the interval 0400-1600 UT on August 31, 1978 strong pc5 activity was observed in the morning and afternoon sector of the magnetosphere. Using data from a world-wide network of ground-magnetometer stations and from the geostationary satellites GEOS 2, GOES 2 and 3 as well as the satellite pair ISEE 1 and 2 a case study was performed with special respect to the question of possible source mechanisms responsible for the observed pulsations. Like earlier workers we came up with the result that the Kelvin-Helmholtz instability at the magnetopause or in the low latitude boundary layer is a likely candidate. In particular we found a change in the azimuthal phase propagation direction from westwards on the morning side and eastward on the afternoon side. Also the sense of polarization and the azimuth of the ground magnetic disturbance in the horizontal plane changed across the meridian of the stagnation point as predicted by a Kelvin-Helmholtz instability source mechanism. A more detailed analysis was carried out for an isolated, large amplitude pc5 event at 1040 UT. At the same time magnetic field observations from the ISEE satellite pair indicate a flux transfer event (FTE) like disturbance at the magnetopause. Also indications of magnetopause boundary oscillations were found, and we feel that this FTE-like event constitutes a possible source for the observed impulsive pc5 event recorded on the ground and on GEOS 2. Furthermore, as the observed pc5 pulsations exhibit a wave-packet structure, we studied whether these wave packets coincided with substorms or substorm intensifications observed simultaneously in the nighttime magnetosphere. However, only a partial one-to-one correlation was found.
ARK: https://n2t.net/ark:/88439/y054611
Permalink: https://geophysicsjournal.com/article/205
ARK: https://n2t.net/ark:/88439/y054611
Permalink: https://geophysicsjournal.com/article/205
Creator (Dublin Core)
Glasmeier, K.H.
Lester, M.
Mier-Jedrzejowicz, W.A.C.
Green, C.A.
Rostoker, G.
Orr, D.
Wedeken, U.
Junginger, H.
Amata, E.
Subject (Dublin Core)
en-US
Geomagnetic pulsations
en-US
Kelvin-Helmholtz instability
en-US
Flux transfer event
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Night-time-daytime coupling of the magnetosphere
en-US
Data
Publisher (Dublin Core)
en-US
Journal of Geophysics
Date (Dublin Core)
1984-08-30
Type (Dublin Core)
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
en-US
Peer-reviewed Article
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/205
Source (Dublin Core)
en-US
Journal of Geophysics; Vol 55 No 1 (1984): Journal of Geophysics; 108-119
2643-2986
2643-9271
Language (Dublin Core)
eng
Relation (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/205/165