title: Torus instability.
abstract: The expansion instability of a toroidal current ring in low-beta magnetized plasma is investigated. Qualitative agreement is obtained with experiments on spheromak expansion and with essential properties of solar coronal mass ejections, unifying the two apparently disparate classes of fast and slow coronal mass ejections.
authors.affiliation: Astrophysical Institute Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Kliem
authors.forename: T
authors.initials: T
authors.lastname: Török