Recent data on transition strengths, namely the hitherto unknown B(E2) values of radioactive ~(140)Nd and ~(142)Sm in the N=80 isotones, have suggested that the proton 1 g_7/2 subshell closure at Z=58 has an impact on the properties of low-lying collective states. The unstable, neutron-rich nuclei ~(140)Nd and ~(142)Sm were investigated via projectile Coulomb excitation at the REX-ISOLDE facility at CERN with the high-purity Germanium detector array MINIBALL. The measurement of ~(140)Nd and the preliminary result for ~(142)Sm demonstrate that the reduced collectivity of ~(138)Ce is a local effect, possibly due to the Z=58 subshell closure, and requests refined theoretical calculations.
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