Estimation of Ion Beam Trajectories for a Slot Aperture Accelerator of Long-Pulse Ion Source in Neutral Beam Injector

Doo-Hee Chang

Nuclear Fusion Engineering & Technology Development Center, Korea Atomic Energy Research Institute, Daejeon, Republic of Korea.

DOI: 10.4236/ojapps.2013.32022                

Abstract

A neutral beam injection (NBI) system has been developed and is being tested for an Experimental Advanced Superconducting Tokamak (EAST) device. The NBI system needs to be employed for an auxiliary heating and current drive of EAST plasmas. The first long pulse ion source (LPIS-1) has been installed in the neutral beam test bed (NBTB) system, and the performance is being tested in the NBTB. The LPIS-1 consists of a magnetic bucket plasma generator with multipole cusp-fields and a set of tetrode accelerators with slit-type apertures (a transparency of 60%). The ion beam trajectories of the accelerator column are estimated for the LPIS-1, including an original structure, with the change of slit aperture distance, plasma grid shape, grid gap distance, and voltage ratio between a plasma grid and a gradient grid using the IGUN code. This kind of calculation for the ion beam trajectory may be useful for the estimation of beam extraction characteristics and the direction of accelerator upgrade or modification, prior to the experiments of ion beam extraction.

Keywords

Long Pulse Ion Source; Slot Aperture Accelerator; EAST; Neutral Beam Injection; Ion Beam Trajectory; IGUN Code

Conflicts of Interest

The authors declare no conflicts of interest.

References

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