Reconnection rate at very high Lundquist number in three dimensions · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Reconnection rate at very high Lundquist number in three dimensions
Plain
In very large, highly conducting plasmas the reconnecting layer breaks into a chain of magnetic bubbles called plasmoids, which speeds reconnection up. In two-dimensional simulations the resulting rate is known, but real systems are three-dimensional, where the bubbles become twisted tubes and turbulence develops.
Precise · changed · core
Revision 1: In resistive (and Hall) MHD reconnection with Lundquist number S = L v_A/eta far above the critical $S_c\sim1e4$, $2\mathrm{D}$ simulations give a rate ~0.01 v_A B_0/c independent of $S$ and a power-law plasmoid size distribution. Determine in $3\mathrm{D}$ the asymptotic rate as $S$ goes to $\infty$, the critical $S_c$, the flux-rope size distribution and whether self-generated turbulence makes the $3\mathrm{D}$ rate differ from the 2D value. An answer is converged $3\mathrm{D}$ values with error bars.
Revision 2: In resistive (and Hall) MHD reconnection with Lundquist number $S = L v_{A}/\eta$ far above the critical $S_{c} \sim 10^{4}$, $2\mathrm{D}$ simulations give a rate $\sim 0.01 v_{A} B_{0}/c$ independent of $S$ and a power-law plasmoid size distribution. Determine in $3\mathrm{D}$ the asymptotic rate as $S$ goes to $\infty$, the critical $S_c$, the flux-rope size distribution and whether self-generated turbulence makes the $3\mathrm{D}$ rate differ from the 2D value. An answer is converged $3\mathrm{D}$ values with error bars.
Settled by
3D MHD simulations converged in S and resolution, cross-checked against a high-S laboratory experiment.
Kind
well-posed
Answer type
value
References
(empty)
Literature status
partially-resolved
Status note
The 2D plasmoid-mediated rate of about 0.01 was established around 2009-2012; the 3D asymptotic regime is still under study in 2025-2026.
Posed since
(empty)

Decisions