Speaker
Description
In recent years, measurements of atomic and nuclear properties have been extended to the heaviest elements that do not occur naturally, using laser spectroscopy and mass spectrometry. Such heavy elements can be produced artificially at heavy-ion accelerator facilities, such as the UNILAC at GSI, but only in extremely small quantities—often at the level of single atoms. This imposes stringent requirements on the sensitivity and efficiency of experimental techniques.
To meet these challenges, we have developed highly sensitive methods that combine laser spectroscopy with buffer-gas stopping cells, in which the reaction products are thermalized and efficiently extracted. Using these techniques, we have investigated the atomic and nuclear properties of several fermium and nobelium isotopes at the SHIP velocity filter at GSI in Darmstadt. These on-line measurements have been complemented by off-line studies at the RISIKO separator at Johannes Gutenberg University Mainz, where long-lived actinide isotopes can be studied by laser spectroscopy with high spectral resolution.
From these experiments, we have obtained precise information on changes in nuclear charge radii as well as nuclear moments across isotopic chains, providing valuable insights into the structure and deformation of heavy nuclei. In addition, we have recently resolved a long-standing question concerning the configuration of the long-lived K=8^- isomer in 254No. By applying laser spectroscopic techniques, we were able to determine its magnetic moment and hence its quasi-particle configuration.
In this presentation, I will introduce the key experimental techniques and present selected results from our most recent experimental campaigns and discuss their implications for our understanding of atomic structure and nuclear properties in the region of the heaviest elements.
| Contribution category | Experiment |
|---|---|
| Presenter status | Faculty/Staff |