Dr Jonathan Morgner Max Planck Institute for Nuclear Physics, now at CERN
Abstract: Stringent tests of bound-state QED with Highly charged tin ions
Presented is a comprehensive experimental study of the bound-electron g-factors in three charge states of highly charged tin ions - hydrogenlike, lithiumlike, and boronlike - performed using the ALPHATRAP Penning-trap setup. These measurements represent the first high-precision determinations of g-factors in tin ions with atomic number Z = 50, extending the reach of quantum electrodynamics (QED) tests via g factors into a previously unexplored regime of strong nuclear electric field. All three g factors were measured with 0.5 parts per billion (ppb) precision. The hydrogenlike measurement provides a stringent test of one-electron QED contributions. With lithiumlike tin we can sensitively probe of interelectronic interactions. The boronlike tin measurement allows for the study of many-electron dynamics with non-zero orbital angular momentum in extreme fields. All three high-precision measurements are the first in the medium-to-high Z regime, marking a major step for tests of fundamental physics in the heavy ion regime. The experimental results are in good agreement with state-of-the-art ab initio QED calculations.