Spatial structures of magnetic depression in the Earth's high-altitude cusp: Cluster multipoint observations
Result description
Magnetic depression structures (magnetic holes) of short time duration from seconds to minutes have been studied using Cluster data in the high-latitude cusp. Our analysis revealed that the magnetic depressions are spatial structures traveling across thespacecraft. We show that multiple properties of the magnetic depressions are consistent with those of mirror structures observed in the magnetosheath or solar wind. The plasma in the cusp is rarely unstable with respect to mirror instability. However, as has been shown by previous studies, once a large magnetic hole is created by mirror instability, it becomes relatively stable and can survive for extended periods of time even if surrounding plasma conditions drop well below the mirror threshold. Specifically, the magnetic holes could be generated in the magnetosheath and enter the cusp due to the open geometry of the cusp magnetic field.
Keywords
high-altitude cuspmirror modesmagnetic holesmulti-spacecraft methods
The result's identifiers
Result code in IS VaVaI
Result on the web
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DOI - Digital Object Identifier
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Alternative languages
Result language
angličtina
Original language name
Spatial structures of magnetic depression in the Earth's high-altitude cusp: Cluster multipoint observations
Original language description
Magnetic depression structures (magnetic holes) of short time duration from seconds to minutes have been studied using Cluster data in the high-latitude cusp. Our analysis revealed that the magnetic depressions are spatial structures traveling across thespacecraft. We show that multiple properties of the magnetic depressions are consistent with those of mirror structures observed in the magnetosheath or solar wind. The plasma in the cusp is rarely unstable with respect to mirror instability. However, as has been shown by previous studies, once a large magnetic hole is created by mirror instability, it becomes relatively stable and can survive for extended periods of time even if surrounding plasma conditions drop well below the mirror threshold. Specifically, the magnetic holes could be generated in the magnetosheath and enter the cusp due to the open geometry of the cusp magnetic field.
Czech name
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Czech description
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Classification
Type
Jx - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP classification
BL - Plasma physics and discharge through gases
OECD FORD branch
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Result continuities
Project
IAA301120601: Investigation of plasma waves in the magnetosphere and in the solar wind
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Z - Vyzkumny zamer (s odkazem do CEZ)
Others
Publication year
2009
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of Geophysical Research
ISSN
0148-0227
e-ISSN
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Volume of the periodical
114
Issue of the periodical within the volume
-
Country of publishing house
US - UNITED STATES
Number of pages
13
Pages from-to
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UT code for WoS article
000270707200001
EID of the result in the Scopus database
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Basic information
Result type
Jx - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP
BL - Plasma physics and discharge through gases
Year of implementation
2009