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arXiv · 2104.12013

Magnetic reconnection as an energy cascade process

S. Adhikari·T. N. Parashar·M. A. Shay·W. H. Matthaeus·P. Sharma Pyakurel·S. Fordin·J. E. Stawarz·J. P. Eastwood
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Abstract

Reconnection and turbulence are two of the most commonly observed dynamical processes in plasmas, but their relationship is still not fully understood. Using 2.5D kinetic particle-in-cell simulations of both strong turbulence and reconnection, we compare the cross-scale transfer of energy in the two systems by analyzing the generalization of the von K\'arm\'an Howarth equations for Hall magnetohydrodynamics, a formulation that subsumes the third-order law for steady cascade rates. Even though the large scale features are quite different, the finding is that the decomposition of the energy transfer is structurally very similar in the two cases. In the reconnection case, the time evolution of the energy transfer also exhibits a correlation with the reconnection rate. These results provide explicit evidence that reconnection itself is fundamentally an energy cascade process.

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S. Adhikari, T. N. Parashar, M. A. Shay, W. H. Matthaeus, P. Sharma Pyakurel, S. Fordin, J. E. Stawarz, J. P. Eastwood. 2021-04-24. Magnetic reconnection as an energy cascade process. https://doi.org/10.1103/physreve.104.065206

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