Application of coherent Rydberg states for collision studies

The cross section for charge transfer in fast collisions between Rydberg atoms in coherent elliptic states of n=25 and singly charged ions has been measured as a function of the eccentricity and the orientation of the initial state. Dramatic variations are seen. Theoretical results based on classical collision dynamics are in good qualitative agreement with the experimental data for initial conditions leading to relatively large cross sections. Quantal close‐coupling results scaled from n=4 to n=25 are in better overall agreement with experiment.