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arXiv · 1509.07743

Spontaneous reconnection at a separator current layer. II. Nature of the waves and flows

Julie E. H. Stevenson·Clare E. Parnell
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Abstract

Sudden destabilisations of the magnetic field, such as those caused by spontaneous reconnection, will produce waves and/or flows. Here, we investigate the nature of the plasma motions resulting from spontaneous reconnection at a 3D separator. In order to clearly see these perturbations, we start from a magnetohydrostatic equilibrium containing two oppositely-signed null points joined by a generic separator along which lies a twisted current layer. The nature of the magnetic reconnection initiated in this equilibrium as a result of an anomalous diffusivity is discussed in detail in \cite{Stevenson15_jgra}. The resulting sudden loss of force balance inevitably generates waves that propagate away from the diffusion region carrying the dissipated current. In their wake a twisting stagnation-flow, in planes perpendicular to the separator, feeds flux back into the original diffusion site (the separator) in order to try to regain equilibrium. This flow drives a phase of slow weak impulsive-bursty reconnection that follows on after the initial fast-reconnection phase.

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Julie E. H. Stevenson, Clare E. Parnell. 2016-01-28. Spontaneous reconnection at a separator current layer. II. Nature of the waves and flows. https://doi.org/10.1002/2015ja021736

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