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arXiv · 1104.0922

Super-Alfvénic propagation of reconnection signatures and Poynting flux during substorms

M. A. Shay·J. F. Drake·J. P. Eastwood·T. D. Phan
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Abstract

The propagation of reconnection signatures and their associated energy are examined using kinetic particle-in-cell simulations and Cluster satellite observations. It is found that the quadrupolar out-of-plane magnetic field near the separatrices is associated with a kinetic Alfvén wave. For magnetotail parameters, the parallel propagation of this wave is super-Alfvénic (V_parallel ~ 1500 - 5500 km/s) and generates substantial Poynting flux (S ~ 10^-5 - 10^-4 W/m^2) consistent with Cluster observations of magnetic reconnection. This Poynting flux substantially exceeds that due to frozen-in ion bulk outflows and is sufficient to generate white light aurora in the Earth's ionosphere.

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M. A. Shay, J. F. Drake, J. P. Eastwood, T. D. Phan. 2011-04-05. Super-Alfvénic propagation of reconnection signatures and Poynting flux during substorms. https://doi.org/10.1103/physrevlett.107.065001

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