| 摘要 |
A charge exchanger comprises a gas-filled housing and generates a neutral beam of radiation from an ions beam entering the housing, by charge exchange caused by resonance collisions between ions and neutral gas; positively charged ions travel along the axis of the housing. An electrical device is incorporated to concentrate the ions of the ions beam close to the axis of the housing. Pref. the electrical device consists of a number of successive transparent gratings each perpendicular to the ions beam and all at negative potential; the absolute (negative) value of the potential increases from each grating to the next in the direction of travel of the beam. The housing is pref. at positive potential, or may comprise a number of sections each at a different positive potential. The beam is focussed or conc. towards the axis, giving improved collimation, and reducing particle loss caused by scatter in the housing. |
