Robust Method for Evaluating Ionization, Charge Exchange and Stripping Cross Sections in Atom-Ion Collisions

Ion-atom charge-changing cross sections are needed in many applications employing the propagation of fast ions through matter. A hybrid method has been developed for calculation of the charge-changing cross sections of ions or atoms by fast ions by combining the quasi-classical approach and the Born approximation of quantum mechanics in the regions of impact parameters in which they are valid, and summing the results to obtain the total cross section [1,2]. As a result, typical computations take only few minutes. This has been tested by comparison with available experimental data and full quantum mechanical calculations. A new scaling formula for the ionization and stripping cross section of atoms and ions by fully stripped projectiles has also been developed [1]. \newline \newline [1] I. D. Kaganovich, E. A. Startsev and R. C. Davidson, ``Formulary and scaling cross sections for ion-atom impact ionization,'' http://arxive.org/abs/physics/0407140. \newline [2] Igor D. Kaganovich, et. al., Nucl. Instr. and Methods A \textbf{544}, 91 (2005).