Physics of Plasmas
A nonaxisymmetric stable magnetohydrodynamic(MHD) equilibrium within a prolate cylindrical conducting boundary has been produced experimentally at Swarthmore Spheromak Experiment (SSX) [M. R. Brown et al., Phys. Plasmas6, 1717 (1999)]. It has m=1toroidal symmetry, helical distortion, and flat λ profile. Each of these observed characteristics are in agreement with the magnetically relaxed minimum magnetic energy Taylor state. The Taylor state is computed using the methods described by A. Bondeson et al. [Phys. Fluids24, 1682 (1981)] and by J. M. Finn et al. [Phys. Fluids24, 1336 (1981)] and is compared in detail to the measured internal magnetic structure. The lifetime of this nonaxisymmetric compact torus (CT) is comparable to or greater than that of the axisymmetric CTs produced at SSX; thus suggesting confinement is not degraded by its nonaxisymmetry. For both one- and two-spheromak initial state plasmas, this same equilibrium consistently emerges as the final state.
C. D. Cothran; Michael R. Brown; T. Gray; M. J. Schaffer; G. Marklin; and Vyacheslav S. Lukin , '00.
"Observation Of A Nonaxisymmetric Magnetohydrodynamic Self-Organized State".
Physics of Plasmas.