The decay energy of Ba¹³³

Abstract

We have redetermined the transition energy for the decay of Ba¹³³ to Cs¹³³ to be 489 keV, confirming Gupta's results, in disagreement with the estimate of 700 keV from beta-decay systematics. The log ft values for the orbital capture transitions to the 437 and 381 keV levels, as well as gamma cascade studies reported previously support a single-particle description for all of the low-lying levels of Cs¹³³, with the possible exception of the one at 158 keV. The doublet splitting between the d3/2 and d5/2 and levels is found to be 300 keV. This splitting and the ground-state quadrupole moment are however not in good agreement with estimates based on a pure single-particle configuration.