Force-free magnetic fields and flares of August 1972

  title={Force-free magnetic fields and flares of August 1972},
  author={K. Tanaka and Y. Nakagawa},
  journal={Solar Physics},
AbstractsOn the basis of observations (Zirin and Tanaka, 1973) inferring the presence of shear in magnetic fields, the amount of extractable energy stored in a class of force-free magnetic fields is evaluated for the flares of August 1972, using the formulations developed by Nakagawa and Raadu (1972). It is shown that the evaluated energy storage could be built up by the proper motions of sunspots in the active region McMath 11976 during July 31 and August 7. Then for the flare of August 7, a… Expand
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