Shell-model investigation of spectroscopic properties and collectivity in the nuclei beyond $^{132}\mathbf{Sn}$
Résumé
The recent shell-model results of even-even chains of nuclei: Te134,136,138,Xe136,138,140,Ba138,140,142,Ce140,142,144, and Nd142,144,146 are explored in this manuscript. The low-lying states energies, E2 and M1 transitions, are investigated using the same effective interaction based on the realistic effective field theory potential N3LO. Significant quadrupole correlations appear in the N=86 isotonic chain, with the signature of nonaxial γband. This class of collectivity is interpreted within the SU(3) symmetries scheme and confirmed by constrained Hartree-Fock shell-model calculations.