Plasma and Fusion Research

Volume 17, 2402056 (2022)

Regular Articles

Effects of Collision Velocity and Mirror Ratio on Collision/Merging Processes of Field-Reversed Configurations
Daisuke HARASHIMA, Tomohiko ASAI, Daichi KOBAYASHI, Taichi SEKI, Tatsuhiro WATANABE and Tsutomu TAKAHASHI
Department of Physics, College of Science and Technology, Nihon University, Tokyo 101-8308, Japan
(Received 10 January 2022 / Accepted 15 March 2022 / Published 13 May 2022)


The effects of collision velocity and mirror ratio on the collision/merging processes of field-reversed configurations (FRCs) were experimentally evaluated. In the collisional merging experiment, the reversal field structure is reformed despite experiencing destructive perturbations resulting from collisions at supersonic/Alfvénic velocity. However, reformation of the reversal field structure was not observed under some experimental conditions, such as slow collision velocity or low mirror ratio. The radial profile of the reversal field structure and its time evolution were observed using an internal magnetic probe array. Collisional merging of FRCs was attempted by adjusting the external field profile. Experimental results suggest the dependence of the trapped poloidal flux of the formed FRC after merging on collision velocity and external magnetic boundary.


field-reversed configuration, collisional merging, mirror ratio, collision velocity

DOI: 10.1585/pfr.17.2402056


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