Local suppression of collectivity in the N=80 isotones at the Z=58 subshell closure

Phys. Rev. C

88
021302(R)
(2013)
C. Bauer, G. Rainovski, N. Pietralla, D. Bianco, A. Blazhev, T. Bloch, S. Bönig, A. Damyanova, M. Danchev, K. A. Gladnishki, T. Kröll, J. Leske, N. Lo Iudice, T. Möller, K. Moschner, J. Pakarinen, P. Reiter, M. Scheck, M. Seidlitz, B. Siebeck, C. Stahl, R. Stegmann, T. Stora, Ch. Stoyanov, D. Tarpanov, M. J. Vermeulen, D. Voulot, N. Warr, F. Wenander, V. Werner, H. De Witte

Background: Recent data on 𝑁=80 isotones have suggested that the proton 𝜋⁡(1⁢𝑔7/2) subshell closure at 𝑍=58 has an impact on the properties of low-lying collective states.

Purpose: Knowledge of the 𝐵⁡(𝐸⁢2;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⁡(𝐸⁢2) 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.

DOI
10.1103/PhysRevC.88.021302
Published on
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