The Magnetic Topology of Solar Eruptions

Here was a breakthrough concept: the "breakout model" of CME initiation. In this model, magnetic stress builds up within a multipolar magnetic structure in a situation in which the field-line connectivities somehow forbid transition to an open state. This cartoon shows the basic geometry of a "delta" sunspot region about to erupt, if you can figure it out; if not please see the full paper. The breakout reconnection happens between the blue and red field lines. The wrinkle of interest to observers here is that the reconnection would not be beneath the arcade-to-be, as in a "tether-cutting" scenario for a bipolar configuration, but instead it would be above the structure that is going to erupt. This implies specific signatures in space and time that occasionally have been claimed as evidence for this picture. Following the decisive step of reconnection in the overlying field, the flare process could develop along ordinary CSHKP lines.