TI: High-Lundquist Number Resistive MHD Simulations of Turbulent Magnetic Reconnection with Secondary Island Formation and Enhanced Reconnection Rate
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HR: 0800h AN: SM51C-1836 Poster TI: High-Lundquist Number Resistive MHD Simulations of Turbulent Magnetic Reconnection with Secondary Island Formation and Enhanced Reconnection Rate AU: *Ragunathan, S EM: [email protected] AF: Geophysical Institute, UAF, Fairbanks, AK, USA AU: Ng, C EM: [email protected] AF: Geophysical Institute, UAF, Fairbanks, AK, USA AB: We present our latest results based on large-scale two dimensional resistive magnetohydrodynamic (MHD) simulations for the magnetic reconnection process in the configuration of island coalescence instability. These simulations are performed using a fairly standard pseudo spectral code, which has been well tested for accuracy, convergence, and compared well with codes using other methods. Cases with a range of Lundquist number S are run using resolutions up to 8192 and thus with S up to 2 × 10. It is found that the reconnection rate is consistent with the Sweet-Parker theory with no tearing instability of the Sweet-Parker current sheet or secondary island (plasmoid) formation when simulations are well resolved and without external noise. However, secondary islands have been observed to form, with faster reconnection rate in simulations superimposed with turbulence (noise). We will present results on the scaling of reconnection rate with S, as well as turbulence levels. This work is supported by a NASA grant NNX08BA71G, and a NSF grant AGS-0962477. DE: [0545] COMPUTATIONAL GEOPHYSICS / Modeling DE: [2723] MAGNETOSPHERIC PHYSICS / Magnetic reconnection DE: [7526] SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY / Magnetic reconnection DE: [7863] SPACE PLASMA PHYSICS / Turbulence SC: SPA-Magnetospheric Physics (SM) MN: 2010 Fall Meeting
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