Conversion electron measurements of isomeric transitions in130,132Teand134Xe

Abstract

In this work microsecond isomers in ${}^{130,132}\mathrm{Te}$ and ${}^{134}\mathrm{Xe}$ are investigated. These nuclei are produced by thermal neutron induced fission of ${}^{239}\mathrm{Pu}$ and ${}^{241}\mathrm{Pu}.$ The detection is based on time correlation between fission fragments selected by the LOHENGRIN spectrometer at ILL (Grenoble) and the $\ensuremath{\gamma}$ rays or conversion electrons from isomers. The ${10}^{+}\ensuremath{\rightarrow}{8}^{+}$ isomeric transition of ${}^{132}\mathrm{Te}$ and ${}^{134}\mathrm{Xe}$ was measured for the first time and the half-life of the analogous transition in ${}^{130}\mathrm{Te}$ was remeasured. The systematic behavior of the $B(E2)$ values of this isomeric transition is studied in Sn, Te, Xe, and Ba isotopes close to ${}^{132}\mathrm{Sn}.$ A simple mechanism is proposed to explain the strong increase in the $B(E2)$ strengths from the Sn to the Te isotones.