Unique parity states in 109Pd as a test of particle-rotor and IBFA models

(n,#betta#) techniques were used to study, for the first time, an essentially complete set of low spin, anti-aligned, unique parity levels in 109Pd. The particle rotor model, notably successful4 for high spin states of the same h/sub 11/2/ parentage in this mass region, did not, and could not, explain the empirical energy levels, even when core asymmetry was included. IBFA calculations involving only two parameters accounted well for both the high spin levels in 105Pd and the low spin states of 109Pd. Analysis of the resulting IBFA wave functions showed large probabilities for core states other than those of the quasi ground band, in particular those associated with the quasi-#betta# band