π(1g7/2) subshell closure at Z = 58 has an impact on the properties of low-lying collective states.
Purpose: Knowledge of the B(E2;2+1→0+1) value of 140Nd is needed in order to test this conjecture.
Method: The unstable, neutron-rich nucleus 140Nd was investigated via projectile Coulomb excitation at the REX-ISOLDE facility with the MINIBALL spectrometer.
Results: The B(E2) value of 33(2) W.u. expands the N = 80 systematics beyond the Z = 58 subshell closure.
Conclusions: The measurement demonstrates that the reduced collectivity of
138Ce is a local effect possibly due to the Z = 58 subshell closure and requests refined theoretical calculations. The latter predict a smoothly increasing trend.