Plasma and Fusion Research

Volume 13, 3401069 (2018)

Regular Articles

Trapping Efficiency of a Non-Adidabatic Confinement Device
Daigo ADACHI, Takaya MATSUI, Shuya IWATA, Toshiki TAKAHASHI and Hiromu MOMOTA1)
Gunma University, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan
National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
(Received 28 December 2017 / Accepted 30 April 2018 / Published 12 June 2018)


We performed trajectory analysis of beam ions in such a magnetic field structure having a weak magnetic field region over a wide range by canceling the magnetic field created by the solenoid coil with a Helmholtz coil. The rate at which the beam ions injected in the axial direction are trapped in the magnetic field structure is statistically examined. In addition, by adjusting the Helmholtz coil current, the position of the field-null point is changed, and the influence on the ion trapping rate is also investigated. As a result, it is found that the larger the beam dispersion, the higher the trapping rate, and the higher the energy, the lower the trapping rate. Furthermore, it is also found that in the case where the magnetic field is not completely canceled at the center of the device, there is an energy which extremely decreases the trapping rate.


Helmholtz coil, non-adiabatic trap, particle separation, trajectory calculation, beam ion

DOI: 10.1585/pfr.13.3401069


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