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arXiv · 1101.3517

Cavitating Langmuir Turbulence in the Terrestrial Aurora

B. Isham·M. T. Rietveld·P. Guio·F. R. E. Forme·T. Grydeland·E. Mjølhus
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Abstract

Langmuir cavitons have been artificially produced in the earth's ionosphere, but evidence of naturally-occurring cavitation has been elusive. By measuring and modeling the spectra of electrostatic plasma modes, we show that natural cavitating, or strong, Langmuir turbulence does occur in the ionosphere, via a process in which a beam of auroral electrons drives Langmuir waves, which in turn produce cascading Langmuir and ion-acoustic excitations and cavitating Langmuir turbulence. The data presented here are the first direct evidence of cavitating Langmuir turbulence occurring naturally in any space or astrophysical plasma.

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B. Isham, M. T. Rietveld, P. Guio, F. R. E. Forme, T. Grydeland, E. Mjølhus. 2012-03-11. Cavitating Langmuir Turbulence in the Terrestrial Aurora. https://doi.org/10.1103/physrevlett.108.105003

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