Nuclear Charge Radii from Precision Bound-Electron g-Factor Measurements

Abstract

An efficient method to determine absolute nuclear charge radii from high-precision bound-electron g-factor measurements in hydrogenlike ions is put forward. Assuming that a nuclear model independent radius determination is possible, we demonstrate that this method can improve the precision of the nuclear radius for several poorly known heavy isotopes by up to two orders of magnitude compared to current literature values, by utilizing recent breakthroughs in the quantum electrodynamics (QED) theory of the bound-electron g-factor [B. Sikora, V. A. Yerokhin, C. H. Keitel, and Z. Harman, Phys. Rev. Lett. 134, 123001 (2025)]. This opens a new, independent pathway for testing nuclear structure models and resolving nuclear structure anomalies.