Magnetic reconnection mechanism for Type II white-light flares
نویسندگان
چکیده
Based on the concept that the heating source for Type II white-light flares (WLFs) may be located in the photosphere, we suggest that Type II WLF is reduced by magnetic reconnection in a weakly ionized plasma. A plasmoid may rise by magnetic buoyancy from the subphotosphere into a sunspot region and then expand to form a current sheet in which a type of resistive instability takes place. The effect of neutral atoms on the resistive instability is estimated and found to produce a growth time of typically ten minutes that agrees well with observations.
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