A1 Journal article (refereed)
Slit extraction and emittance results of a permanent magnet minimum-B quadrupole electron cyclotron resonance ion source (2024)
Kosonen, S., Kalvas, T., Koivisto, H., Tarvainen, O., & Toivanen, V. (2024). Slit extraction and emittance results of a permanent magnet minimum-B quadrupole electron cyclotron resonance ion source. Nuclear Instruments and Methods in Physics Research. Section B : Beam Interactions with Materials and Atoms, 546, Article 165147. https://doi.org/10.1016/j.nimb.2023.165147
JYU authors or editors
Publication details
All authors or editors: Kosonen, Sami; Kalvas, Taneli; Koivisto, Hannu; Tarvainen, Olli; Toivanen, Ville
Journal or series: Nuclear Instruments and Methods in Physics Research. Section B : Beam Interactions with Materials and Atoms
ISSN: 0168-583X
eISSN: 1872-9584
Publication year: 2024
Publication date: 04/11/2023
Volume: 546
Article number: 165147
Publisher: Elsevier
Publication country: Netherlands
Publication language: English
DOI: https://doi.org/10.1016/j.nimb.2023.165147
Publication open access: Openly available
Publication channel open access: Partially open access channel
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/91827
Abstract
We present an experimental and simulation study of high charge state ion beams produced with a permanent magnet electron cyclotron resonance ion source (ECRIS) with minimum-B quadrupole magnetic field topology and slit extraction system. The unconventional topology generates fan-shaped plasma flux, favouring a rectangular aperture for beam extraction. We demonstrate successful low-energy transport of the slit beam, achieving up to 25 times higher beam currents compared to a round extraction aperture. Maximum beam intensities are 1.5 and 15 μA for argon 11+ and 9+, respectively. The results indicate microwave power-limited beam production. Emittance values are comparable to traditional ECRIS. Unlike in conventional ECRIS, the emittance increases monotonically with increasing charge state due to slit extraction, magnetic topology, and beam transport characteristics. The experimental transport efficiency for helium ranges from 32% to 50%, depending on the total beam current. The losses primarily occur due to the dipole magnet’s insufficient vertical aperture.
Keywords: particle accelerators; cyclotrons; plasma physics
Free keywords: ion source; electron cyclotron resonance; ion beam; plasma confinement; emittance; beam extraction
Contributing organizations
Related projects
- The effect of magnetic field configuration on the performance of minimum-B ECR ion source
- Koivisto, Hannu
- Research Council of Finland
Ministry reporting: Yes
VIRTA submission year: 2024
Preliminary JUFO rating: 2