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Lyapunov Exponent Analysis for Stochastic Ion Motion in a Non-Adiabatic Trap

Ryo MATSUMOTO, Shuya IWATA, Takahiro URANO, Kojiro SEKIGUCHI, Gaku SAKAI and Toshiki TAKAHASHI

Gunma University, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan

(Received 30 September 2018 / Accepted 9 January 2019 / Published 12 February 2019)

Abstract

The Lyapunov exponent analysis is carried out for ion motions in a non-adiabatic trap where the axial magnetic field from a solenoid is partially cancelled by that from a Helmholtz coil. In particular, relation between the Lyapunov exponents and the trapped rate of ions injected in the axial direction is numerically studied. It is found that there exist energy minimizing the particle trapped rate, and the Lyapunov exponent for the axial velocity is found to be minimized with that energy.

Copyright (c) 2019 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

non-adiabatic trap, Helmholtz coil, stochastic motion, particle-tracking calculation, Lyapunov exponent analysis

DOI: 10.1585/pfr.14.2401035

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References

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