Quasi-resonant charge exchange collisions between multiply charged ions

Cross section calculations of the quasi-resonant ion-ion charge exchange reaction A^Z++B^(Z+1)+ to A^(Z+1)++B^Z++ Delta epsilon (1<or=Z<or=5, Delta epsilon <<1 au) are performed for some Tokamak plasma impurity ions. It is demonstrated that, in the 10-50 keV energy range, the rate of production of A^(Z+1)+ by the above reaction may become comparable with the electron-A^Z+ ionisation rate when the ratio of the concentrations of the B^(Z+1)+ ions and the plasma electrons is of the order of 10^-1-10^-2.