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

92
054326
(2015)
R. Stegmann, C. Bauer, G. Rainovski, N. Pietralla, C. Stahl, S. Bönig, S. Ilieva, A. Blazhev, A. Damyanova, M. Danchev, K. Gladnishki, J. Jolie, R. Lutter, J. Pakarinen, D. Radeck, E. Rapisarda, P. Reiter, M. Scheck, B. Siebeck, T. Stora, P. Thöle, T. Thomas, M. Thürauf, M. J. Vermeulen, D. Voulot, N. Warr, F. Wenander, V. Werner, H. De Witte

It was shown that the evolution of the 𝐵⁡(𝐸⁢2;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⁡(𝐸⁢2) 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⁡(𝐸⁢2;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⁡(𝐸⁢2) value of 32⁢(4)⁢W.u. reflects the impact of the 𝜋⁡(1⁢𝑔7/2⁡2⁢𝑑5/2) subshell closure at 𝑍=64 with respect to a linear scaling of collectivity with valence proton number.

DOI
10.1103/PhysRevC.91.054326
Published on
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