To extract intense ion beams with good beam optics from ion sources, controlling the distance deff between the plasma meniscus (i.e., beam emission surface) and the beam extraction grid is important. This study conducts a novel investigation into the dependence of the effective distance deff on the amount of surface H̄ production SH-. For this purpose, a 3D PIC (three dimensional Particle-in-Cell) simulation is conducted to obtain a model geometry of the extraction region for a H̄ ion source with SH- as a parameter. Based on results, deff significantly depends on SH- and the H̄-electron density ratio (α = nH̄=ne) in front of the extraction aperture for the same plasma density; as SH- increases, deff decreases.
|Journal||Plasma and Fusion Research|
|Publication status||Published - 2023|
- negative ion source
- plasma meniscus
- surface-produced ion
ASJC Scopus subject areas
- Condensed Matter Physics