Dynamical contributions to the quantum defects of calcium

Abstract
Nonadiabatic effects on the structure of Rydberg states of alkaline-earth atoms are examined and found to be large in many cases. Calculations for the quantum defects of the singlet F and G series in calcium, including dynamical contributions, are shown to be in good agreement with recent experimental data. This is in contrast to predictions based on the adiabatic core-polarization model, which significantly overestimates the quantum defects. Values for quantum defects of Ca for l4 are presented.