Asymptotic relativistic and QED corrections for helium Rydberg states

Significant differences exist between theory and high precision measurements for transition frequencies among the n = 10 states of helium. The asymptotic expanion for relativistic corrections based on a core polarization model is extended. It is shown that new terms of order (x-5) arise from the perturbing effect of the -αd/x4 asymptotic potential on the Rydberg electron. The new terms substantially reduce differences between variational and asymptotic predictions, thereby providing a strong confirmation of both. In addition, a asymptotic expansion for the QED shift is developed by calculating the perturbing effect of the Rydberg electron on the Lamb shift of the 1s electron. A global asymptotic formula for contributions to the energies and comparisons with experiment will be presented