Theoretical Study of Atomic Rydberg States

Abstract

Recently, a new microwave-optical method was developed by Wing and Lamb¹for the experimental study of the atomic Rydberg states. The new technique, with a 10⁴ -fold improvement in resolution over the conventional spectroscopic methods, makes it possible for the first time to obtain accurate details on the previously unresolved electrostatic fine structures. As emphasized by those authors, the physics of the atomic Rydberg states holds special theoretical interest not only because of its quasi-hydrogenic nature but also because of its close relation to the scattering of slow electrons by the charged ion core. Thus the experimental breakthrough has added great impetus to the search for a parallel progress in theory, the search for a general, first-principle approach, capable of improved quantitative predictions as well as qualitative interpretations. As an attempt along this direction, we have carried out a theoretical study on the electrostatic fine structure of the Rydberg series for atomic helium within the framework of the Brueckner-Goldstone² many-body perturbation theory approach.