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Observation of inertial energy cascade in interplanetary space plasma

Luca Sorriso-Valvo·Raffaele Marino·Vincenzo Carbone·Fabio Lepreti·Pierluigi Veltri·Alain Noullez·Roberto Bruno·Bruno Bavassano·Ermanno Pietropaolo
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Abstract

We show in this article direct evidence for the presence of an inertial energy cascade, the most characteristic signature of hydromagnetic turbulence (MHD), in the solar wind as observed by the Ulysses spacecraft. After a brief rederivation of the equivalent of Yaglom's law for MHD turbulence, we show that a linear relation is indeed observed for the scaling of mixed third order structure functions involving Elsässer variables. This experimental result, confirming the prescription stemming from a theorem for MHD turbulence, firmly establishes the turbulent character of low-frequency velocity and magnetic field fluctuations in the solar wind plasma.

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Luca Sorriso-Valvo, Raffaele Marino, Vincenzo Carbone, Fabio Lepreti, Pierluigi Veltri, Alain Noullez, Roberto Bruno, Bruno Bavassano, Ermanno Pietropaolo. 2007-02-09. Observation of inertial energy cascade in interplanetary space plasma. https://doi.org/10.1103/physrevlett.99.115001

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