Measurement of the ground-state lambshift of hydrogenlike uranium at the electron cooler of the ESR

Abstract

Abstract. X-rays are emitted with the radiative recombination of free electrons in an electron cooler of a heavyion storage ring. Due to a small width of the X-ray lines, an observation angle close to 0 ° and an accurate determination of the ion velocity, the ground-state Lambshift of hydrogenlike uranium (470 _+ 16) eV could be measured to an accuracy of 3.4%. A re-evaluation of a measurement of the lsl/2 Lambshift in hydrogenlike gold gave a new value of (202.3 + 7.9) eV as compared to the former value of(212 + 15) eV. The results are in excellent agreement with QED calculations and are more precise than any other measurements previously reported for a high-Z, hydrogenlike ion.

Two-time Green's function method in quantum electrodynamics of high-Z few-electron atoms

“…The uncertainty of the Dirac binding energy results from the uncertainty of the Rydberg constant [146]. As can be deduced from the table, the present status of the experimental precision on the ground-state Lamb shift in hydrogenlike uranium [147][148][149] provides a test of QED in first order in α on the level of about 5%.…”

Testing high-Z QED with SuperEBIT: An estimate of the two-loop Lamb shift based on a measurement of the – transition in

“…The y-axis shows the experimental accuracy of given measurement divided by the size of the total QED contributions. The 1s measurements are from (Briand et al, 1990;Sto¨hlker et al, 1993;Lupton et al, 1994;Beyer et al, 1995;Sto¨hlker et al, 2000;Gumberidze et al, 2005). The 2s measurements are from (Munger and Gould, 1986;Schweppe et al, 1991;Beiersdorfer et al, 1993Beiersdorfer et al, , 1995Beiersdorfer et al, , 1998Brandau et al, 2003;Beiersdorfer et al, 2005).…”

QED theory of the spectral line profile and its applications to atoms and ions

“…After inserting the widths it corresponds to the amplitude Eq. (89). Separating out this term we can rewrite Γ…”

“…The recent experimental accuracy achieved in the Lamb shift measurements in heavy H-like ions [87][88][89][90] requires to take into account in theoretical calculations the complete set of two-loop radiative corrections, depicted in Fig. 4.…”