Présidents de session
Session 10: New isomeric decay modes
- Filip Kondev (ANL, Lemont, USA)
The well-explored A~190 Hf-Ta-W nuclei near the valley of stability feature robust axially symmetric prolate shapes and associated high-K isomerism. The very-neutron-rich isotopes of these elements are far less explored experimentally as they cannot be accessed via fusion-evaporation or neutron-transfer reactions, and varying predictions of prolate-to-oblate shape transitions in different...
In 2021, the MAJORANA DEMONSTRATOR experiment concluded its investigation into neutrinoless double beta decay involving $^{76}$Ge. Proven to be one of the world's ultra-low-background facilities, we adapted the apparatus to explore the rare decay of a distinct isotope. Notably, in nature $^{180m}$Ta stands as the sole known isotope existing in an isomeric state rather than the ground state. ...
The radioisotope thorium-229 features a nuclear isomer with an exceptionally low excitation energy of ≈ 8.3 eV and a favourable coupling to the environment, making it a candidate for a next generation of optical clocks allowing to study fundamental physics such as the variation of the fine structure constant [1,2]. While first indirect experimental evidence for the existence of such a nuclear...
First-order electromagnetic processes are the primary mechanism by which excited states in atomic nuclei relax, most-often via single γ-ray emission. Since both the initial- and final-state wave functions possess a well-defined spin and parity, conservation laws impose a characteristic multipolarity for each discrete transition. Nature favours pathways that proceed via the lowest-available...
The `island' of fission isomers identified in the actinide region (Z = 92 - 97, N = 141- 151) originates from multi-humped fission barriers, which can be understood as the result of superimposing microscopic shell corrections to the macroscopic liquid drop model description. For the first time, the in-flight fragmentation and electromagnetic dissociation methods were applied at GSI for...
