A1 Journal article (refereed)
A study of VUV emission and the extracted electron-ion ratio in hydrogen and deuterium plasmas of a filament-driven H−/D− ion source (2019)


Komppula, J.; Tarvainen, O.; Kalvas, T.; Koivisto, H.; Myllyperkiö, P.; Toivanen, V. (2019). A study of VUV emission and the extracted electron-ion ratio in hydrogen and deuterium plasmas of a filament-driven H−/D− ion source. Physics of Plasmas, 26, 7, 073517. DOI: 10.1063/1.5095475


JYU authors or editors


Publication details

All authors or editors: Komppula, J.; Tarvainen, O.; Kalvas, T.; Koivisto, H.; Myllyperkiö, P.; Toivanen, V.
Journal or series: Physics of Plasmas
ISSN: 1070-664X
eISSN: 1527-2419
Publication year: 2019
Volume: 26
Pages range: 7
Article number: 073517
Publisher: AIP Publishing LLC
Publication country: United States
Publication language: English
Open Access: Publication channel is not openly available
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/65185


Abstract

Vacuum ultraviolet (VUV) emission diagnostics for studying differences of electron impact processes in hydrogen and deuterium plasmas are presented. The method is applied to study a filament driven multicusp arc discharge negative ion source by comparing the VUV-emission intensities of different emission bands and extracted currents of H−/D− ions and electrons. It was found that the ratio of coextracted electrons to extracted ions is four times higher for deuterium than for hydrogen. No significant differences of the VUV-spectra or volumetric rates of ionization, excitation, production of high vibrational states, and dissociation were found between the plasmas of the two isotopes. The volumetric rates of these electron impact processes are presented for both discharges. It is concluded that in the filament ion source, the observed difference of H−/D− production through dissociative electron attachment is due to different diffusion rates across the magnetic fields of the tandem-type discharge chamber rather than the production rate of ground state molecules at their vibrational levels.

Free keywords: isotopes; ion sources; plasma diagnostics; vibrational states; electron impact ionization; electric discharges; plasma spectroscopy; electron impact emission spectroscopy; vacuum ultraviolet radiation; diffusion rate


Contributing organizations


Ministry reporting: Yes
Preliminary JUFO rating: 1

Last updated on 2019-01-08 at 14:33