Effect of Coulomb collision on the negative ion extraction mechanism in negative ion sources.
Rev Sci Instrum
; 87(2): 02B918, 2016 Feb.
Article
em En
| MEDLINE
| ID: mdl-26932090
ABSTRACT
To improve the H(-) ion beam optics, it is necessary to understand the energy relaxation process of surface produced H(-) ions in the extraction region of Cs seeded H(-) ion sources. Coulomb collisions of charged particles have been introduced to the 2D3V-PIC (two dimension in real space and three dimension in velocity space particle-in-cell) model for the H(-) extraction by using the binary collision model. Due to Coulomb collision, the lower energy part of the ion energy distribution function of H(-) ions has been greatly increased. The mean kinetic energy of the surface produced H(-) ions has been reduced to 0.65 eV from 1.5 eV. It has been suggested that the beam optics of the extracted H(-) ion beam is strongly affected by the energy relaxation process due to Coulomb collision.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article