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| Titel |
Model for Reduced Power Spectra of Critically Balanced Solar Wind Turbulence with Damping by Kinetic Alfvén Waves. |
| VerfasserIn |
Anne Schreiner, Joachim Saur, Michael von Papen, Olga Alexandrova, Catherine Lacombe |
| 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 |
250150405
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| Publikation (Nr.) |
 EGU/EGU2017-14863.pdf |
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| Zusammenfassung |
| The observed spectral structure of magnetic turbulence at electrons scales in the solar wind is
still not sufficiently understood. Analytical dissipation models for solar wind turbulence
are usually derived in the three-dimensional wavenumber space. However, in-situ
observations of magnetic fluctuations are obtained in a reduced form in the frequency
space, where various wavevectors contribute to the spectral energy density at a
certain frequency. Due to this sampling effect, dissipation processes at electron scales
influence the spectral scaling of the sub-ion range particularly for small field-to-flow
angles.
Based on a forward modeling approach by von Papen & Saur (2015), we calculate reduced
spectral energy densities from a three-dimensional energy distribution in wavenumber space
under the assumption of critically balanced turbulence and damping via wave-particle
interactions of kinetic Alfvén waves. The damping is described through the imaginary part of
the kinetic Alfvén wave frequency, which we obtain from linear Vlasov theory. We compare
the spectral energy densities to a set of observations in frequency space obtained from
magnetic field measurements of the Cluster spacecraft analyzed in Alexandrova et al. (2012). |
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