O–H charge exchange in cold, dense hydrogen plasmas

It is pointed out that the accidentally resonant charge-exchange reaction, O + + H 0 ⇄ O 0 + H + , is an important mechanism for causing the loss of singly charged oxygen ions from oxygen-contaminated hydrogen plasmas. Results of a Monte Carlo simulation are presented which show that the fraction of oxygen lost because of charge exchange exceeds 1/3 when the parameters n e ∼ 10 13 cm −3 , n H 0 ∼ 10 11 cm −3 and T e ∼ 3 eV are attained. This process may be important in determining impurity losses from the edge plasmas of tokamaks.