Quasi-Periodic Pulsations in Solar and Stellar Flares. Review

A wonderful array of places (within a cartoon flare/CME) in which quasi-periodic pulsations QPP might occur or find sustenance. A full dozen of them, including the humble circuit diagram (No. 5). One of the more interesting aspects of this is the fact that more or less simple flares, without any of the eruption/arcade trimmings, almost always show pulsations. But with the trimmings, one can immediately see that the normal modes may have great complexity.! The Archivist particularly likes the cartoon behavior shown in red (Mechanism No. 7), in which slow-mode waves somehow mediate different loops and thus keep the whole arcade from collapsing on an the Alfvén time scale.