Plasmoids formation during simulations of coaxial helicity injection in the National Spherical Torus Experiment

Abstract

Formation of an elongated Sweet-Parker current sheet and a transition to plasmoid instability has for the first time been predicted by simulations in a large-scale toroidal fusion plasma in the absence of any pre-existing instability. Plasmoid instability is demonstrated through resistive MHD simulations of transient Coaxial Helicity Injection (CHI) experiments in the National Spherical Torus Experiment (NSTX).Consistent with the theory, fundamental characteristics of the plasmoid instability, including fast reconnection rate, have been observed in these realistic simulations. Motivated by the simulations, experimental camera images have been revisited and suggest the existence of reconnecting plasmoids in NSTX. Global, system-size plasmoid formation observed here should also have strong implications for astrophysical reconnection, such as rapid eruptive solar events.

5 pages, 5 figures

References in corpus (3)

• Instability of current sheets and formation of plasmoid chains
• Self-Feeding Turbulent Magnetic Reconnection on Macroscopic Scales
• A catastrophe model for fast magnetic reconnection onset

Cited by in corpus (7)

• General Theory of the Plasmoid Instability
• Magnetic reconnection in the era of exascale computing and multiscale experiments
• Plasmoid Instability in Forming Current Sheets
• Dynamo-driven plasmoid formation from a current-sheet instability
• An Alfvenic reconnecting plasmoid thruster
• Effects of Plasmoid Formation on Sawtooth Process in a Tokamak
• Onset of Plasmoid Reconnection during Magnetorotational Instability