Comparison of ion source plasma responses to extraction grid bias between hydrogen and deuterium operations in NIFS-RNIS
Open Access
- 1 April 2022
- conference paper
- Published by IOP Publishing in Journal of Physics: Conference Series
- Vol. 2244 (1) , 012046
Abstract
An isotope effect of negative ion motion in plasma near a plasma grid (PG), which is a plasma-beam boundary grid, has been investigated in a negative hydrogen-ion source with the surface production process of the negative ion on the PG surface. Negative deuterium-ion (D-) density was higher than negative hydrogen-ion (H-) density in the condition without extraction-grid bias (V egb) and approached the H- density in the condition with V egb. Thus, the D- density responded stronger than the H- density to the V egb. The density of the negative hydrogen-ion isotopes and the density response to the V egb have been organized into respective identical trends by momenta of isotopes emitting from the PG. The Larmor motion can be a dominant mechanism of the negative ion transport from the PG to the plasma.Keywords
This publication has 6 references indexed in Scilit:
- Achievement of the ITER NBI ion source parameters for hydrogen at the test facility ELISE and present Status for deuteriumFusion Engineering and Design, 2020
- Spatial distribution of negative ion density near the plasma gridReview of Scientific Instruments, 2020
- Exploring deuterium beam operation and the behavior of the co-extracted electron current in a negative-ion-based neutral beam injectorNuclear Fusion, 2019
- Effect of Coulomb collision between surface produced H− ions and H+ ions on H− extraction mechanism and beam optics in a Cs-seeded H− ion source by 3D particle in cell modelJournal of Applied Physics, 2018
- Response of H− ions to extraction field in a negative hydrogen ion sourceFusion Engineering and Design, 2017
- Cavity Ringdown Technique for negative-hydrogen-ion measurement in ion source for neutral beam injectorJournal of Instrumentation, 2016