Heidelberg 1999 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
A: Atomphysik
A 3: Spektroskopie II
A 3.4: Talk
Monday, March 15, 1999, 17:15–17:30, TE2
Numerische Berechnung der Lamb Shift für kleine Kernladung — •Ulrich Jentschura1, Peter Mohr2, and Gerhard Soff1 — 1Institut für Theroretische Physik, TU Dresden, 01062 Dresden — 2National Institute of Standards and Technology, Gaithersburg MD20899, USA
We present a high-precision numerical evaluation of the self energy in hydrogenlike ions with the low nuclear charge numbers Z = 1-5. The difference between the sum of the analytically evaluated terms up to the order of α (Zα)6 and our all-order numerical result is 28 kHz for atomic hydrogen and 3200 kHz for He+. The numerical calculation is non-perturbative in the external binding field, and we obtain results for the self-energy remainder function GSE(Zα) with a precision of roughly 0.8 Hz for hydrogen and 13 Hz for ionized helium. Resummation and convergence acceleration techniques are used in the calculation. The numerical techniques lead to a reduction in computer time by three orders of magnitude and thereby remove the principal numerical difficulties associated with the singularity of the relativistic propagators for nearly equal radial arguments.