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| Titel |
Quiet-Time Suprathermal (∼0.1 - 200 keV) Electrons in the Solar Wind |
| VerfasserIn |
Linghua Wang, Liu Yang, Jiawei Tao, Qiugang Zong, Gang Li, Robert Wimmer-Schweingruber, JianSen He, Chuanyi Tu, Stuart Bale |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250139029
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| Publikation (Nr.) |
 EGU/EGU2017-2191.pdf |
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| Zusammenfassung |
| We present a statistical survey of the energy spectrum of solar wind suprathermal (∼0.1-200
keV) electrons measured by the WIND 3DP instrument at 1 AU during quiet times at the
minimum and maximum of solar cycles 23 and 24. The observed energy spectrum of both
(beaming) strahl and (isotropic) halo electrons at ∼0.1-1.5 keV generally fits to a
Kappa distribution function with an index κ and effective temperature Teff, while
the observed energy spectrum of nearly isotropic superhalo electrons at ∼20-200
keV generally fits to a power-law function, J ∼ E−β. We find a strong positive
correlation between κ and Teff for both strahl and halo electrons, and a strong positive
correlation between the strahl density and halo density. In both solar cycles, κ is larger at
solar minimum than at solar maximum for both strahl and halo electrons. For the
superhalo population, the spectral index β ranges from ∼1.6 to ∼3.7 and the integrated
density nsup ranges from 10−8 cm−3 to 10−5 cm−3, with no clear association
with the sunspot number. In solar cycle 23 (24), the distribution of β has a broad
maximum between 2.4 and 2.8 (2.0 and 2.4). All the strahl, halo and superhalo
populations show no obvious correlation with the solar wind core population. These
results reflect the nature of the generation of solar wind suprathermal electrons. |
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