Publikace na Matematicko-fyzikální fakulta |
2020
Abstrakt
Quantum electrodynamical (QED) calculations of ionization energies of the 1snd D states are performed for the helium atom. We reproduce the previously known relativistic and QED effects up to order m alpha(5) and extend the theory by calculating the complete m alpha(6) correction.
The total contribution of the m alpha(6) effects is shown to be much smaller than previously estimated, due to a large cancellation between the radiative and nonradiative parts of this correction. As a result of our calculations, we confirm the previously reported deviations between measured transition energies and theoretical predictions for the nD-2S and nD-2P transitions.
Possible reasons for this discrepancy are analyzed.