2014 Fiscal Year Final Research Report
Cesium recycling in the large cesiated negative ion source
Project/Area Number |
25820444
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Nuclear fusion studies
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Research Institution | Japan Atomic Energy Agency |
Principal Investigator |
YOSHIDA Masafumi 独立行政法人日本原子力研究開発機構, 核融合研究開発部門 那珂核融合研究所, 研究員 (80638825)
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Project Period (FY) |
2013-04-01 – 2015-03-31
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Keywords | 核融合 / 負イオン中性粒子入射装置 / セシウム / プラズマ |
Outline of Final Research Achievements |
For clarification of Cs recycling in large cesiated negative ion source, time evolution of spatial profile of negative ion production during an initial conditioning phase has been experimentally investigated in the JT-60 negative ion source, where a Cs nozzle is installed in the center of the negative ion source. Up to 0.4 g Cs injection, there is no enhancement of the negative ion production and no observation of the Cs emission signal in the source, suggesting the injected Cs is mainly deposited on the water-cooled wall near the nozzle. After 0.4 g Cs injection, enhancement of the negative ion production appeared only at the central segment of the PG. The expansion of the area of the surface production was saturated after ~2 g Cs injection. From the results, it is found that Cs ionization and its transport plays an important role for the negative ion production. In addition, Cs, which is absorbed on the inner wall, is desorbed at more than 340 K.
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Free Research Field |
プラズマ加熱
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