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AR 8210: “ Live & Let Die”? Or, “Never Say Never Again”?. Several techniques exist to determine flows from magnetograms, to drive coronal models. Time series of vector magnetograms can be used with: FLCT, ILCT (Welsch et al . 2004), MEF (Longcope 2004), MSR (Georgoulis & LaBonte 2006),
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Several techniques exist to determine flows from magnetograms, to drive coronal models. • Time series of vector magnetograms can be used with: • FLCT, ILCT (Welsch et al. 2004), • MEF (Longcope 2004), • MSR (Georgoulis & LaBonte 2006), • DAVE (Schuck, 2006), or • LCT (e.g., Démoulin & Berger 2003) to find • Several methods have been used with AR 8210 data, but not on the same magnetograms / same cadence, etc. Standardizing data & comparing results would be good.
In ideal MHD, photospheric flows move mag-netic flux with a flux transport rate, Bnuf. (1) Demoulin & Berger (2003): Apparent motion of flux on a surface can arise from horizontal and/or vertical flows. In either case, uf represents “flux transport velocity.”
Magnetic diffusivity also causes flux transport, as field lines can slip through the plasma. • Even non-ideal transport can be represented as a flux transport velocity. • Quantitatively, one can approximate 3-D non-ideal effects as 2-D diffusion, in Fick’s Law form,
