Evolution of quadrupole collectivity in N=80 isotones toward the Z=64 subshell gap: The B(E2; 2+1→0+1) value of 142Sm
Phys. Rev. C
It was shown that the evolution of the 𝐵(𝐸2;2+
1→0+
1) values in 𝑁 = 80 isotones from Te to Nd is affected by the underlying subshell structure. This manifests itself in the observation of the local suppression of the 𝐵(𝐸2) value at 𝑍=58 with respect to the neighboring nuclei
136
Ba
and
140
Nd
. To investigate this shell sensitivity toward the 𝑍=64 subshell gap, the 𝐵(𝐸2;2+
1→0+
1) value of the unstable nucleus
142
Sm
was measured utilizing the projectile Coulomb excitation technique. The radioactive ion beam (RIB) experiment was performed at the REX-ISOLDE facility at CERN. The 𝐵(𝐸2) value of 32(4)W.u. reflects the impact of the 𝜋(1𝑔7/22𝑑5/2) subshell closure at 𝑍=64 with respect to a linear scaling of collectivity with valence proton number.