High-spin states up to I~22, 37/2 and 24ћ have been studied in the 134,135Ba (Z=56) and 120Te (Z=52) nuclei respectively. The reaction used to populate 134Ba and 135Ba high-spin states was 124Sn(14C,4n and 3n) at a beam energy of 57 and 50 MeV respectively. High-spin states in 120Te were populated using the 110Pd(14C,4n) reaction at a beam energy of 64 MeV. Through these reactions and using the FSU gamma-ray detector array of Compton suppressed Ge detectors, significant extensions to the level schemes for each of these nuclei were made.
In 134Ba, a large number of states are observed for the first time beyond the 10+ isomer. The most prominent feature of the 134Ba level scheme is the newly discovered dipole (Δ I=1) band (group P). This structure is interpreted as oblate collective rotational in character with the configuration πg7/2 h11/2υh11/2-2. Comparisons with neighboring nuclei leading to this interpretation are discussed.
Previous to the present study only a handful of gamma-ray transitions had been assigned to 135Ba. In the present work a level scheme with over 25 new transitions and 24 new levels has been constructed for this nucleus. In the 135Ba level scheme the prominent feature is another dipole (ΔI=1) band (group F). This band is interpreted as the 3 quasiparticle configuration πh11/2g7/2υh11/2-1. Another interesting structure of this nucleus is the 21/2 level of group K which carries a substantial fraction (14%) of the decay intensity. This long lived level is interpreted as analogous to the 10+ isomeric state in 134Ba.
New structures in 120Te have been identified at high spin which indicate a transition to oblate non-collective structure. These observations are consistent with Cranked Nilsson Strutinsky calculations which predict specific favored configurations for high-spin states.