Electric Charge State Changing Collisions of Hydrogen and Helium with Low-Z Impurity Particles Part I. Charge Exchange Processes

This report contains a collection of practical approximating formulas for one-electron loss and one-electron capture cross-sections of ion-atom and ion-ion collisions of H0, H+, He0, He+ and He2+ particles with Li, Be, B, C and Ne neutral atoms and all of their positive ions. The report consists of two parts treating charge exchange and ion impact ionization collisions respectively. The results are mainly based on theoretical calculations by CAPTURE, CDW, and ARSENY numerical codes. Independent experimental and theoretical results were taken into account where available. The primary objective of this work is to provide the necessary background concerning atomic processes essential for localized fusion plasma diagnostics based on light impurity pellet injection. As for passive line-integral diagnostics of energetic proton and a-particle energy distributions, impurities contribute to both the source function and the attenuation rate of neutral atom fluxes escaping from the plasma. Impurities also play a significant role in the high energy neutral atom heating beam stopping in the plasma. The analytic cross-section fits for a wide energy range presented here may be useful in the numerical modeling and in the experimental data analysis.