Optimum extracted H− and D− current densities from gas‐pressure‐limited high‐power hydrogen/deuterium tandem ion sources

The tandem hydrogen/deuterium ion source is modeled for the purpose of identifying the maximum current densities that can be extracted subject to the gas‐pressure constraints proposed for contemporary beam‐line systems. Optimum useful extracted current densities are found to be in the range of approximately 7–10 mA cm−2. The sensitivity of these current densities is examined subject to uncertainties in the underlying atomic/molecular rate processes. A principal uncertainty remains the quantification of the molecular vibrational distribution following H+3 wall collisions.

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