Observation of the hyperfine transition in lithium-like Bismuth ${}^{209}{\text{Bi}}^{80+}$: Towards a test of QED in strong magnetic fields

Matthias Lochmann, Raphael Jöhren, Christopher Geppert +21

We performed a laser spectroscopic determination of the $2s$ hyperfine splitting (HFS) of Li-like ${}^{209}{\text{Bi}}^{80+}$ and repeated the measurement of the $1s$ HFS of H-like $^{…