Numerical analysis of the production profile of H atoms and subsequent H ions in large negative ion sources

Takado, Naoyuki*; Tobari, Hiroyuki; Inoue, Takashi; Hanatani, Junji*; Hatayama, Akiyoshi*; Hanada, Masaya; Kashiwagi, Mieko; Sakamoto, Keishi

The production and transport processes of H atoms are numerically simulated using a three-dimensional Monte Carlo transport code. The code was applied to the large JAEA 10 ampere negative ion source under the Cs-seeded condition to obtain a spatial distribution of surface-produced H ions. In the H atom transport process, the energy relaxation of the H atoms, which affects the surface H ion production rate, is taken into account. The result indicates that the surface H ion production is enhanced near the high-electron-temperature region where H atom production is localized.