Non-yrast states in 125Xe

The non-yrast states of ¹²⁵Xe have been investigat with the ¹²²Te(α, n) and ¹²³Te(α, 2n) reactions by means of in-beam γ-spectroscopy using a setup of 6 Compton-suppressed high-purity-germanium (HPGe)detectors. Over 400 new transitions establishing over 110 new levels could be placed in a level scheme totalling 196 levels connected by 563 transitions. 77 spin and parity assignments were made (some of them tentatively) and 35 multipolarity mixing ratios could be assigned to transitions using the γ-angular distribution, γ-linear polarization, γγ-DCO-analysis and γ-excitation-function methods. The negativeparity data are compared to the predictions of the rigid-triaxial-rotor-plus-particle model and the interacting-boson-fermion model. Both calculations describe successfully the excitation energies of these non-yrast states. The branching ratios of the lower non-yrast states are also reproduced very well. Only at the fourth and higher excited states of a given spin, a discrepancy between experiment and theory was observed.