Journal article
Swarm in situ observations of F region polar cap patches created by cusp precipitation
Geophysical research letters, Vol.42(4), pp.996-1003
02/28/2015
DOI: 10.1002/2014GL062610
Abstract
High‐resolution in situ measurements from the three Swarm spacecraft, in a string‐of‐pearls configuration, provide new insights about the combined role of flow channel events and particle impact ionization in creating F region electron density structures in the northern Scandinavian dayside cusp. We present a case of polar cap patch formation where a reconnection‐driven low‐density relative westward flow channel is eroding the dayside solar‐ionized plasma but where particle impact ionization in the cusp dominates the initial plasma structuring. In the cusp, density features are observed which are twice as dense as the solar‐ionized background. These features then follow the polar cap convection and become less structured and lower in amplitude. These are the first in situ observations tracking polar cap patch evolution from creation by plasma transport and enhancement by cusp precipitation, through entrainment in the polar cap flow and relaxation into smooth patches as they approach the nightside auroral oval.
Key Points
Novel technique using string‐of‐pearls spacecraft to resolve plasma dynamics
In situ Swarm observations of the creation and evolution of polar cap patches
Cusp ionization can dominate the creation and initial structuring of patches
Details
- Title: Subtitle
- Swarm in situ observations of F region polar cap patches created by cusp precipitation
- Creators
- L. V Goodwin - University of SaskatchewanB Iserhienrhien - University of SaskatchewanD. M Miles - University of AlbertaS Patra - University of OsloC Meeren - University of BergenS. C Buchert - Swedish Institute of Space PhysicsJ. K Burchill - University of CalgaryL. B. N Clausen - University of OsloD. J Knudsen - University of CalgaryK. A McWilliams - University of SaskatchewanJ Moen - University of Oslo
- Resource Type
- Journal article
- Publication Details
- Geophysical research letters, Vol.42(4), pp.996-1003
- DOI
- 10.1002/2014GL062610
- ISSN
- 0094-8276
- eISSN
- 1944-8007
- Number of pages
- 8
- Grant note
- Radio and Space Plasma Physics Group at the University of Leicester Norwegian Research Council (230935) Canadian NSERC PGSD2 graduate scholarship Research Council of Norway (230996) European Space Agency Norwegian Centre for International Cooperation in Education (SiU) (NNA‐2012/10099) Canadian Space Agency
- Language
- English
- Date published
- 02/28/2015
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984199765102771
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