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arXiv · 1907.06802

In-situ observation of Hall Magnetohydrodynamic Cascade in Space Plasma

Riddhi Bandyopadhyay·Luca Sorriso-Valvo·Alexandros Chasapis·Petr Hellinger·William H. Matthaeus·Andrea Verdini·Simone Landi·Luca Franci·Lorenzo Matteini·Barbara L. Giles·Daniel J. Gershman Craig J. Pollock·Christopher T. Russell·Robert J. Strangeway·Roy B. Torbert·Thomas E. Moore·James L. Burch
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Abstract

We present estimates of the turbulent energy cascade rate, derived from a Hall-MHD third-order law. We compute the contribution from the Hall term and the MHD term to the energy flux. We use MMS data accumulated in the magnetosheath and the solar wind, and compare the results with previously established simulation results. We find that in observation, the MHD contribution is dominant at inertial scales, as in the simulations, but the Hall term becomes significant in observations at larger scales than in the simulations. Possible reasons are offered for this unanticipated result.

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Riddhi Bandyopadhyay, Luca Sorriso-Valvo, Alexandros Chasapis, Petr Hellinger, William H. Matthaeus, Andrea Verdini, Simone Landi, Luca Franci, Lorenzo Matteini, Barbara L. Giles, Daniel J. Gershman Craig J. Pollock, Christopher T. Russell, Robert J. Strangeway, Roy B. Torbert, Thomas E. Moore, James L. Burch. 2019-07-16. In-situ observation of Hall Magnetohydrodynamic Cascade in Space Plasma. https://doi.org/10.1103/physrevlett.124.225101

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