Plasma and Fusion Research

Volume 17, 2402092 (2022)

Regular Articles

Improvement of Plasmoid Acceleration Performance by Increased Magnetic Pressure Gradient for High-Mach Number Shock Generation
Taichi SEKI, Tomohiko ASAI, Daichi KOBAYASHI, Tatsuhiro WATANABE, Daisuke HARASHIMA, Yasuaki TAMURA, Hiroki SOMEYA, Tsutomu TAKAHASHI and Jordan MORELLI1)
Department of Physics, College of Science and Technology, Nihon University, Tokyo 101-8308, Japan
1)
Department of Physics, Engineering & Astronomy, Queen's University, Kingston, Ontario K7L 3N6, Canada
(Received 10 January 2022 / Accepted 6 June 2022 / Published 22 July 2022)

Abstract

The field-reversed configuration (FRC) collisional merging experiment in the FAT-CM device at Nihon University has been conducted for the generation of collisionless shock waves that are considered to cause the generation of nonthermal particles. Two FRC-like plasmoids with extremely high-beta formed by field-reversed theta-pinch are translated directly toward each other and collide at super-sonic/Alfvénic velocity. The acceleration performance is improved to generate high-Mach number shocks by generating the high-magnetic pressure gradient at the boundary between the formation and confinement sections. In this study, an increase in the translation velocity in the shortened coil geometry is presented. Changing of coil geometry may affect not only the velocity but also other parameters.

Keywords

collisionless shock, high-Mach number, field-reversed configuration, high-beta plasma, acceleration

DOI: 10.1585/pfr.17.2402092

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