Experiments on a reflex‐type sheet plasma negative‐ion source

National Institute for Fusion Science, Nagoya 464‐01, Japan
Review of Scientific Instruments (Impact Factor: 1.61). 02/1990; DOI: 10.1063/1.1141267
Source: IEEE Xplore


Negative hydrogen ions are extracted from a reflex‐type sheet plasma. Electron density and temperature profiles are measured with changing the filling gas pressure, and they are optimized to the H- production at the optimum gas pressure. The optimum gas pressure is 5 mTorr for the discharge current I d =2 A. As the discharge current I d increases, H- current increases linearly corresponding to the density increase in the center region, but saturates above I d =40 A. The maximum extracted H- current density of 4 mA/cm2 is obtained at I d =100 A.

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