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arXiv · 1302.1749

Identification of intermittent multi-fractal turbulence in fully kinetic simulations of magnetic reconnection

E. Leonardis·S. C. Chapman·W. Daughton·V. Roytershteyn·H. Karimabadi
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Abstract

Recent fully nonlinear, kinetic three-dimensional simulations of magnetic reconnection [Daughton et al. 2011] evolve structures and exhibit dynamics on multiple scales, in a manner reminiscent of turbulence. These simulations of reconnection are among the first to be performed at sufficient spatio-temporal resolution to allow formal quantitative analysis of statistical scaling which we present here. We find that the magnetic field fluctuations generated by reconnection are anisotropic, have non-trivial spatial correlation and exhibit the hallmarks of finite range fluid turbulence; they have non-Gaussian distributions, exhibit Extended Self-Similarity in their scaling and are spatially multifractal. Furthermore, we find that the field J.E is also multifractal, so that magnetic energy is converted to plasma kinetic energy in a manner that is spatially intermittent. This suggests that dissipation in this sense in collisionless reconnection on kinetic scales has an analogue in fluid-like turbulent phenomenology, in that it proceeds via multifractal structures generated by an intermittent cascade.

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E. Leonardis, S. C. Chapman, W. Daughton, V. Roytershteyn, H. Karimabadi. 2013-02-07. Identification of intermittent multi-fractal turbulence in fully kinetic simulations of magnetic reconnection. https://doi.org/10.1103/physrevlett.110.205002

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