Numerical analysis of the spatial nonuniformity in a Cs-seeded H{sup -} ion source
- Faculty of Science and Technology, Keio University, Hiyoshi, Yokohama 223-8522 (Japan)
The H{sup -} ion production and transport processes are numerically simulated to clarify the origin of H{sup -} beam nonuniformity. The three-dimensional transport code using the Monte Carlo method has been applied to H{sup 0} atoms and H{sup -} ions in the large 'JAERI 10A negative ion source' under the Cs-seeded condition, in which negative ions are dominantly produced by the surface production process. The results show that a large fraction of hydrogen atoms is produced in the region with high electron temperature. This leads to a spatial nonuniformity of H{sup 0} atom flux to the plasma grid and the resultant H{sup -} ion surface production. In addition, most surface-produced H{sup -} ions are extracted even through the high T{sub e} region without destruction. These results indicate a correlation between the production process of the H{sup -} ion and the spatial nonuniformity of the H{sup -} ion beam.
- OSTI ID:
- 20779018
- Journal Information:
- Review of Scientific Instruments, Vol. 77, Issue 3; Conference: 11. international conference on ion sources, Caen (France), 12-16 Sep 2005; Other Information: DOI: 10.1063/1.2172356; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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