Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas

0504118 - ÚFP 2020 RIV US eng J - Journal Article
Réfy, D. - Zoletnik, S. - Dunai, D. - Anda, G. - Lampert, M. - Hegedüs, S. - Nagy, D. - Palánkai, M. - Kádi, J. - Leskó, B. - Aradi, M. - Háček, Pavel - Weinzettl, Vladimír
Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas.
Review of Scientific Instruments. Roč. 90, č. 3 (2019), č. článku 033501. ISSN 0034-6748. E-ISSN 1089-7623
R&D Projects: GA MŠMT(CZ) LM2015045
Institutional support: RVO:61389021
Keywords : ABP * COMPASS * Li-beam
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 1.480, year: 2019
Method of publishing: Limited access
https://aip.scitation.org/doi/10.1063/1.5084219

Atomic beam probe is an extension of the routinely used beam emission spectroscopy diagnostic for the plasma edge current fluctuation measurement at magnetically confined plasmas. Beam atoms ionized by the plasma are directed to a curved trajectory by the magnetic field and may be detected close to the wall of the device. The arrival location and current distribution of the ions carry information about the plasma current distribution, the density profile, and the electric potential in the plasma edge. This paper describes a micro-Faraday cup matrix detector for the measurement of the few microampere ion current distribution close to the plasma edge. The device implements a shallow Faraday cup matrix, produced by printed-circuit board technology. Secondary electrons induced by the plasma radiation and the ion bombardment are basically confined into the cups by the tokamak magnetic field. Additionally, a double mask is installed in the front face to limit the ion influx into the cups and supplement secondary electron suppression. The setup was tested in detail using a lithium ion beam in the laboratory. Switching time, cross talk, and fluctuation sensitivity test results in the lab setup are presented along with the detector setup to be installed at the COMPASS tokamak.
Permanent Link: http://hdl.handle.net/11104/0295819