Relativistic and radiative energy shifts for Rydberg states
Abstract
We investigate relativistic and quantum electrodynamic effects for highlyexcited bound states in hydrogenlike systems (Rydberg states). In particular, hydrogenic oneloop Bethe logarithms are calculated for all circular states (l = n  1) in the range 20 <= n <= 60 and successfully compared to an existing asymptotic expansion for large principal quantum number n. We provide accurate expansions of the Bethe logarithm for large values of n, for S, P and circular Rydberg states. These three expansions are expected to give any Bethe logarithm for principal quantum number n > 20 to an accuracy of five to seven decimal digits, within the specified manifolds of atomic states. Within the numerical accuracy, the results constitute unified, general formulae for quantum electrodynamic corrections whose validity is not restricted to a single atomic state. The results are relevant for accurate predictions of radiative shifts of Rydberg states and for the description of the recently investigated laserdressed Lamb shift, which is observable in a strong coherentwave light field.
 Publication:

Journal of Physics B Atomic Molecular Physics
 Pub Date:
 January 2005
 DOI:
 10.1088/09534075/38/2/008
 arXiv:
 arXiv:physics/0406015
 Bibcode:
 2005JPhB...38S..97J
 Keywords:

 Physics  Atomic Physics
 EPrint:
 8 pages