Theory of the energy levels and precise two-photon spectroscopy of atomic hydrogen and deuterium

Abstract

In last few years significant progress has been achieved both in the experimental technique and the theoretical methods for the determination of the energy levels of simple hydrogenic systems. We review recent two-photon spectroscopic measurements performed in Garching and the relevant theoretical predictions for the hydrogen energy levels. Good agreement is achieved when all theoretical contributions are included, showing the importance of recently calculated higher order corrections.

Nature of the darwin term and (zα)4m3/M2contribution to the lamb shift for an arbitrary spin of the nucleus

“…In particular, we cannot agree with the conclusion that the Darwin term is absent for a particle with spin 1, made in Ref. [1] (see also [2]). The subject becomes of real interest now for interpreting the high precision experiments in atomic spectroscopy [3,4,5].…”

Higher-order binding corrections to the Lamb shift of 2Pstates

“…One is the classic 2S 1/2 -2P 1/2 Lamb shift measured by several groups [20], [21], [19], and the second is the combined Lamb shift L(4S − 2S) − 1 4 L(2S − 1S) as measured by the Hänsch group (for a review see [22]). The experimental value of 2S Lamb shift can be extracted from E(2S-2P 1/2 ) having the precise value for 2P 1/2 Lamb shift, and can also be determined from the combined Lamb shift through the formula…”

Higher-order nuclear-polarizability corrections in atomic hydrogen

“…This is dominated by 1 The logarithmic mean-excitation energies are calculated using a trick [25]. We define a quantity closely related to α E…”