Testing Shell Stabilization at N = 80; $g$ factor of the 2$^{+}_{1}$ state in $^{138}$Ce

ORAL

Abstract

The study of observed mixed symmetry states in N = 80 isotones, namely $^{134}$Xe, $^{136}$Ba and $^{138}$Ce manifest a large effect of single-particle structure on the evolution of these collective excitations. The observed fragmentation of $M1$ transition strength between the (2$_{1,ms}^{+}$) state and the ($2_{1,fs}^{+}$) state in $^{138}$Ce and the largely unfragmented strength in $^{134}$Xe and $^{136}$Ba was attributed to the presence of a $\pi g_{7/2}$ subshell closure at $Z=58$. To prove the validity of this proposed concept of shell stabilization, the $g$ factor of the 2$^{+}_{1}$ in $^{138}$Ce was measured. The low-lying excited states in $^{138}$Ce were populated via inverse Coulomb excitation at ATLAS, ANL. To measure the $g$ factor, the recoil into vacuum technique was used and attenuation of the angular distribution of emitted 2$^{+}_{1}\rightarrow0^{+}\gamma$ rays was measured. The results of the ongoing analysis will be presented providing a constraint on the single-particle wavefunctions contributing to the collective states in the N = 80 isotones and guide theory in developing a consistent and predictive picture of the underlying single-particle dynamics.

Authors

  • F. Naqvi

    • Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06511, USA
  • V. Werner

    • Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06511, USA
  • T. Ahn

    • Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06511, USA/NSCL, MSU, USA
  • G. Ilie

    • Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06511, USA
  • N. Cooper

    • Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06511, USA
  • D. Radeck

    • Institut fuer Kernphysik, University of Cologne, 50937 Cologne, Germany
  • M.P. Carpenter

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • C.J. Chiara

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • F. Kondev

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • T. Lauritsen

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • C.J. Lister

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • D. Seweryniak

    • Argonne National Laboratory, Argonne, IL 60439, USA
  • S. Zhu

    • Argonne National Laboratory, Argonne, IL 60439, USA