Numerical studies on optimization of volume produced H＾- ions in a low-pressure negative ion source.

体積生成型水素負イオン源の最適化に関する数値計算

Numerical studies on optimization of volume produced H＾- ions in a low-pressure negative ion source.

Creators Fukumasa Osamu

Production of H^- ions in a steady state hydrogen discharge plasma is discussed. According to the numerical calculation of a set of particle balance equations, H^- ionsare formed mainly by dissociative attachment of slow plasma electrons (i. e. electron temperature T_e ≒ 1 eV) to highly vibrationally excited hydrogen molecules H_2 ^* (optimum vibrational level v” = 7-9), and those H_2^* (v”) are produced mainly by collisional excitation due to fast primary electrons with energies in excess of 40 eV. On enhancement of H^- yield, the effect of other H_2^* (v”) formation process caused by molecular ions or by atomic hydrogen is also discussed. Although H_2^* (v”) is essential to the H^- formation, the optimum plasma conditions for the H_2^* (v”) production are not compatible with those for the H^- formation. In order to clarify the effectiveness of a tandem two-chamber system, the relative H^- yields for single-chamber and tandem two-chamber systems are compared.

(c)プラズマ・核融合学会()

[ISSN]0451-2375

[NCID]AN00039568

[isVersionOf] [URI]https://www.jstage.jst.go.jp/article/jspf1958/60/6/60_6_419/_article/-char/ja/