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arXiv · 1507.03830

Precision Test of Many-Body QED in the Be$^+$ $2p$ Fine Structure Doublet Using Short-Lived Isotopes

Wilfried Nörtershäuser·Christopher Geppert·Andreas Krieger·Krzysztof Pachucki·Mariusz Puchalski·Klaus Blaum·Mark L. Bissell·Nadja Frömmgen·Michael Hammen·Magdalena Kowalska·Jörg Krämer·Kim Kreim·Rainer Neugart·Gerda Neyens·Rodolfo Sánchez·Deyan T. Yordanov
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Abstract

Absolute transition frequencies of the $2s\; ^2{\rm S}_{1/2} \rightarrow 2p\;^2\mathrm{P}_{1/2,3/2}$ transitions in Be$^+$ were measured for the isotopes $^{7,9-12}$Be. The fine structure splitting of the $2p$ state and its isotope dependence are extracted and compared to results of \textit{ab initio} calculations using explicitly correlated basis functions, including relativistic and quantum electrodynamics effects at the order of $m \alpha^6$ and $m \alpha^7 \ln \alpha$. Accuracy has been improved in both the theory and experiment by 2 orders of magnitude, and good agreement is observed. This represents one of the most accurate tests of quantum electrodynamics for many-electron systems, being insensitive to nuclear uncertainties.

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Wilfried Nörtershäuser, Christopher Geppert, Andreas Krieger, Krzysztof Pachucki, Mariusz Puchalski, Klaus Blaum, Mark L. Bissell, Nadja Frömmgen, Michael Hammen, Magdalena Kowalska, Jörg Krämer, Kim Kreim, Rainer Neugart, Gerda Neyens, Rodolfo Sánchez, Deyan T. Yordanov. 2015-07-14. Precision Test of Many-Body QED in the Be$^+$ $2p$ Fine Structure Doublet Using Short-Lived Isotopes. https://doi.org/10.1103/physrevlett.115.033002

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