Speaker
Description
Isotope shift measurements and the King plot are an established method to determine the nuclear charge radius [1]. Nonlinear effects in King plots have recently gained additional interest as probes for higher-order nuclear deformation and beyond-standard-model physics [2,3]. Methods like the generalized King plot allow to extract multiple effects such as higher-order nuclear deformation and couplings to ultra-light dark matter [4]. For these contributions, high-precision measurements of the isotope shift in multiple narrow transitions between multiple isotope pairs are required and many alkali-earth atoms and singly charged ions show a suitable atomic structure. However, the amount of spinless stable isotopes is a limiting factor. Measurements have been performed at highest precision in stable Yb and Ca [5,6]. In order to overcome the limitation in stable isotopes, deceleration and spectroscopy of radioactive ion beams for precision isotope shift spectroscopy is discussed in this contribution. Strontium ions are chosen as proof-of-concept and the implementation of fluorescence spectroscopy of the S1/2 ↔ D3/2 and S1/2 ↔ D5/2 transitions is propounded.
[1] W. H. King, Isotope Shifts in Atomic Spectra. Springer US, (1984).
[2] J. C. Berengut et al., Phys. Rev. Lett., 120, 091801 (2018).
[3] Flambaum, V. V., et al., Phys. Rev. A 97, 032510 (2018).
[4] J. C. Berengut et al., Phys. Rev. Research, 2, 4 (2020)
[5] Door, M. et al., Phys. Rev. Lett. 134, 063002 (2025).
[6] 1. Wilzewski, A. et al., Phys. Rev. Lett. 134, 233002 (2025).
