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arXiv · 1707.08180

Magnetosperic Multiscale (MMS) observation of plasma velocity-space cascade: Hermite representation and theory

S. Servidio·A. Chasapis·W. H. Matthaeus·D. Perrone·F. Valentini·T. N. Parashar·P. Veltri·D. Gershman·C. T. Russell·B. Giles·S. A. Fuselier·T. D. Phan·J. Burch
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Abstract

Plasma turbulence is investigated using high-resolution ion velocity distributions measured by the Magnetospheric Multiscale Mission (MMS) in the Earth's magnetosheath. The particle distribution is highly structured, suggesting a cascade-like process in velocity space. This complex velocity space structure is investigated using a three-dimensional Hermite transform that reveals a power law distribution of moments. In analogy to hydrodynamics, a Kolmogorov approach leads directly to a range of predictions for this phase-space cascade. The scaling theory is in agreement with observations, suggesting a new path for the study of plasma turbulence in weakly collisional space and astrophysical plasmas.

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S. Servidio, A. Chasapis, W. H. Matthaeus, D. Perrone, F. Valentini, T. N. Parashar, P. Veltri, D. Gershman, C. T. Russell, B. Giles, S. A. Fuselier, T. D. Phan, J. Burch. 2017-07-25. Magnetosperic Multiscale (MMS) observation of plasma velocity-space cascade: Hermite representation and theory. https://doi.org/10.1103/physrevlett.119.205101

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