Current disruption and its spreading in collision-less magnetic reconnection

ORAL

Abstract

Recent magnetic reconnection experiments (MRX) [Dorfman et al., Geophys. Res. Lett. 40, 233 (2012)] have disclosed current disruption in the absence of guide field. During current disruption in MRX, current density and total out-of-reconnection-plane current drop simultaneous with a rise in out-of-reconnection-plane electric field. Here we show that current disruption is an intrinsic property of dynamic formation of X-point configuration of magnetic field in magnetic reconnection, independent of the model used for plasma description and of dimensionality (2-D or 3-D) of reconnection. An analytic expression for the current drop is derived from Ampere's equation and its predictions are verified by 2-D and 3-D electron-magnetohydrodynamic (EMHD) simulations. Three dimensional EMHD simulations show that the current disruption due to localized reconnection spreads along the direction of electron flow with a speed which depends on the wave number of the perturbation. The implications of these results for MRX and other reconnection experiments will be presented.

*This work was partially funded by the Max-Planck/Princeton Center for Plasma Physics.

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Authors

  • Neeraj Jain

    • Max Planck Institute for Solar System Research, 37191, Katlenburg-Lindau, Germany

  • Joerg Buechner

    • Max Planck Institute for Solar System Research, 37191, Katlenburg-Lindau, Germany

  • Seth Dorfman

    • UCLA
    • University of California, Los Angeles, CA 90095, USA

  • Hantao Ji

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Physics Laboratory, Princeton, NJ 08543
    • Princeton Plasma Physics Laboratory, Princeton University
    • Princeton Plasma Physics Laboratory, Princeton, New Jersey, USA
    • Princeton Plasma Physics Lab

  • A. Surjalal Sharma

    • Department of Astronomy, University of Maryland, College Park, MD, USA