Solar flares: Models and predictions of the flux-rope theory

The magnetic structures of flare models have hitherto been limited to those parts above the solar surface. The submerged sections, together with their magnetic stresses and hydromagnetic effects, have been ignored. This neglect is a natural result of the traditional theory (including the turbulent dynamo theory) of solar fields, according to which submerged fields are controlled by the convective motions and so have no important hydromagnetic effects. The flux-rope-fiber theory, on the contrary, is based on powerful submerged flux ropes composed of innumerable individually twisted flux fibers. This structure provides a foundation for models of flares and associated effects and may aid in their prediction. (1) Flares with an impulsive phase require the emergence within a dome-shaped magnetic structure of a second bipolar region of reverse polarity. This previously improbable ''arcade of sheared loops'' is modeled simply with a kink-unstable flux element whose individual flux fibers provide the fibrous structure of a classival two-ribbon flare preceded by a kark filament. (2) The flux-rope sections beneath a pair of sunspots unwind by transferring twist into the atmospheric magnetic field. The sections fray, and their widely spread flux fibers are twisted into S-shapes, which are observed as dark filaments and flare ribbons. (3) The twists in flux fibers and other flux elements are greatly enhanced after emerging. Contact between parallel elements provides current sheets and various flare structures. (4) The same structure account for a variety of mass ejecta and interplanetary waves. Erupting prominences and the largest interplanetary blasts may result from the upward transfer of large amounts of helical twists. (5) The use of these models for flare prediction is discussed. (6) Contributions to the low-temperature flare by Alfven waves are discussed further