Laser Spectroscopy for the Study of Exotic Nuclei

TL;DR

Laser spectroscopy has significantly advanced the understanding of exotic, unstable nuclei by measuring fundamental properties like spins and moments, aiding theory validation and enabling studies of nuclei near the driplines with ongoing technological improvements.

Contribution

This paper reviews recent developments and applications of laser spectroscopy techniques in studying exotic nuclei, including innovative molecular methods and future prospects at advanced facilities.

Findings

Laser spectroscopy determines nuclear spins, moments, and charge radii with high precision.

It provides critical tests for nuclear many-body theories and nucleon interactions.

Recent molecular spectroscopy techniques open new research avenues for short-lived nuclei.

Abstract

Investigation into the properties and structure of unstable nuclei far from stability remains a key avenue of research in modern nuclear physics. These efforts are motivated by the continual observation of unexpected structure phenomena in nuclei with unusual proton-to-neutron ratios. In recent decades, laser spectroscopy techniques have made significant contributions in our understanding of exotic nuclei in different mass regions encompassing almost the entire nuclear chart. This is achieved through determining multiple fundamental properties of nuclear ground and isomeric states, such as nuclear spins, magnetic dipole and electric quadrupole moments and charge radii, via the measurement of hyperfine structures and isotope shifts in the atomic or ionic spectra of the nuclei of interest. These properties, when measured with sufficient precision for a long range of isotopes, offer prominent tests of recently developed state-of-the-art theory and help to stimulate new developments to improve the many-body methods and nucleon-nucleon interactions at the core of these models. With the aim of exploring more exotic short-lived nuclei located ever closer to the proton and neutron driplines, laser spectroscopy techniques, with their continuous technological developments towards higher resolution and higher sensitivity, are extensively employed at current- and next-generation radioactive ion beam facilities worldwide. Ongoing efforts in parallel promise to make even more exotic species available for study at next-generation facilities. Very recently, an innovative application of laser spectroscopy on molecules containing short-lived nuclei has been demonstrated offering additional opportunities for several fields of research, e.g. fundamental symmetry studies and astrophysics.