Levels in¹³⁶Te and new high-spin states in neutron-rich N=84 isotones

Abstract

Excited states have been identified for the first time in the neutron-rich nuclide 136Te by observing prompt gamma -rays from 252Cf spontaneous fission fragments. The technique of triple gamma -ray coincidences was used for the first time in a spontaneous fission study to identify 136Te. In addition, new high-spin states in N=84 138Xe (12+) and 140Ba (8+) and N=86 140Xe (10+) have been observed. These provide the first high-spin yrast band systematics for the N=84 isotones.