Orateur
Description
The experimental information available to test shell-model calculations south of 208Pb is almost non-existent at present due to the challenges in accessing the exotic neutron-rich region around and beyond N=126. Such information are essential not only for understanding how the shell structure evolves below and beyond N=126, and if deformation or new shell gaps develop in the region, but to calculate more complex configurations in the more exotic, inaccessible nuclei on the r-process pathway towards the trans-bismuth fissile elements [Hol19].
In the present contribution, we will show for the first time new isomeric transitions observed in the “south-east” quadrant of 208Pb in an experiment carried out during the 2021 spring campaign of the BRIKEN collaboration at the RIBF factory in RIKEN (Japan) [Wu17,Tol19]. The level schemes will be discussed in terms of the latest shell-model calculations in the region [Yuan22]. Future perspectives to continue with the investigation of isomerism around and beyond 208Pb exploiting the BigRIPS spectrometer at RIKEN will be discussed as well.
References
[Hol19] E.M. Holmbeck et al., Ap. J. 870, 23 (2019)
[Tol19] A. Tolosa-Delgado et al., Nucl. Instr. And Methods A, 925-133 (2019)
[Wu17] J. Wu et al., β-decay spectroscopy in the vicinity of the N=126 closed shell. RIBF NP-PAC Proposal NP1712-RIBF158
[Yuan22] Cenxi Yuan et al., Phys. Rev. C 106, 044314 (2022)
