Microscopic description of radioactivity : from cluster states to 2 $\alpha$ decay

IJCLab
Fri, Oct. 15th 2021, 11:00
Bat 703, p 45, CEA Saclay, Orme des Merisiers

Among the various approaches to the nuclear many-body problem, a covariant formulation of the energy density functional (cEDF) method has proven able to successfully describe both quantum liquid-like and cluster-like properties of atomic nuclei (nature of the excited states, energy/radius of the ground/excited states, transition probability, ...). Emission processes such as fission and cluster-radioactivity, interpreted as an extremely asymmetric fission process, were also extensively studied within the EDF framework. It provided both a qualitative understanding and a quantitative description of these decay modes.
On the other hand, a microscopic description of  $alpha$-radioactivity was missing, until its recent formulation within the cEDF framework, where it appears as an even more extremely asymmetric fission process. The $alpha$-decay properties of the mid-mass nuclei $^{108}$Xe and $^{104}$Te were tackled using the cEDF machinery and found to be consistent with the experimental data. The cEDF approach thus provides a powerful framework not only for tackling nuclear structure features, but also for describing, in a unified way, the various processes by which a nucleus is emitted, from $alpha$ and cluster radioactivities to fission.Within this frame, a new exotic radioactive mode was recently predicted, under the form of two $alpha$-particles emitted back-to-back. The corresponding lifetime was computed for two different nuclei and found to be close to what is observed for cluster-radioactivity. Therefore,  the confirmation or refutation of the existence of a two-$alpha$ decay-mode could be amenable to current experimental investigations.

Le séminaire se tiendra en présentiel en salle 135
et simultanément en visio : https://cern.zoom.us/j/9856735938?pwd=UjZST0ZBRXRqeWFDQ0czQ1J3aWRQdz09

https://cern.zoom.us/j/9856735938?pwd=UjZST0ZBRXRq...
Contact : Loïc THULLIEZ