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| Titel |
High-frequency and intermittent Alfvénic turbulence in the solar wind |
| VerfasserIn |
Jinsong Zhao, Yuriy Voitenko, Dejin Wu, Mingyang Yu |
| 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 |
250143404
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| Publikation (Nr.) |
 EGU/EGU2017-7120.pdf |
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| Zusammenfassung |
| Alfvénic turbulent cascade perpendicular and parallel to the background magnetic field is
studied accounting for anisotropic dispersive effects and turbulent intermittency. The
perpendicular dispersion and intermittency make the perpendicular-wavenumber magnetic
spectra steeper and speed up production of high ion-cyclotron frequencies by the turbulent
cascade. On the contrary, the parallel dispersion makes the spectra flatter and decelerate the
frequency cascade above the ion-cyclotron frequency. Competition of these factors results in
spectral indices distributed in the interval [-2,-3], where -2 is the index of high-frequency
space-filling turbulence, and -3 is the index of low-frequency intermittent turbulence formed
by tube-like fluctuations. Spectra of fully intermittent turbulence fill a narrower
range of spectral indices [-7/3,-3], which almost coincides with the range of indexes
measured in the solar wind. This suggests that the kinetic-scale turbulent spectra
are mainly shaped by the dispersion and intermittency. A small mismatch with
measured indexes of about 0.1 can be associated with damping effects not studied here. |
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