Negative hydrogen ion production in fusion dedicated ion sources

作者：Bacal M^*

来源：Chemical Physics, 2012, 398: 3-6.

DOI：10.1016/j.chemphys.2011.04.002

• Negative ion source
• Caesium ionization
• Positive hydrogen ion

A brief description is given of the basic processes in negative ion sources dedicated to fusion. It is considered that in these sources negative ions are produced by ions and atoms interacting with a caesiated surface, but this mechanism is not unique: the volume production, based on dissociative electron attachment to rovibrationally excited molecules, is also active. We suggest that in RF sources the acceleration of positive ions to a few tens of eV by the plasma potential difference between the driver and the extraction regions can have an important effect on negative ion production by enhancing the negative ion yield from caesiated surfaces, and by charge exchange reactions with caesium atoms. The presence of energetic positive ions can have other implications (modifying the virtual cathode in front of the plasma grid, participating in caesium ionization).

• 出版日期2012-4-4